Some new class of Chaplygin Wormholes
Traversable wormholes Some simple examples
arXiv:0809.0907v1 [gr-qc] 4 Sep 2008
Matt Visser
Theoretical Division T–8, Mail Stop B–285 Los Alamos National Laboratory Los Alamos, New Mexico 87545 Present address: School of Mathematics, Statistics, and Computer Science Victoria University of Wellington, New Zealand
matt.visser@
A 23 January 1989; L TEX-ed September 4, 2008
Abstract Building on the work of Morris, Thorne, and Yurtsever, some particularly simple examples of traversable wormholes are exhibited. These examples are notable both because the analysis is not limited to spherically symmetric cases, and because it is possible to in some sense minimize the use of exotic matter. In particular, it is possible for a traveller to traverse such a wormhole without passing through a region of exotic matter. As in previous analyses, the weak energy condition is violated in these traversable wormholes. PACS numbers: 04.20.Jb, 03.70.+k, 04.62.+v, 04.60.-m, 11.10.Kk Keywords: traversable wormholes, Lorentzian wormholes. Physical Review D39 (1989) 3182–3184. DOI: 10.1103/PhysRevD.39.3182
五年级英语作文昆虫生长过程英文
五年级英语作文昆虫生长过程英文全文共5篇示例，供读者参考篇1The Amazing Life of InsectsHey there! Did you know that insects are some of the coolest little critters on our planet? They might be tiny, but their lives are full of amazing adventures and crazy transformations. Let me tell you all about the incredible life cycle of insects!It all starts with the egg stage. Insect moms lay tons of small eggs, sometimes in cool hidden spots to keep them safe. The eggs can be really tiny, but they're packed with everything a baby insect needs to get going. After a while of just chilling in the egg, the insect finally hatches!When the insect first hatches, it's called a larva. Larvae look pretty different from the adult insects. Some are kinda like little worms, while others might resemble tiny dragons or aliens. The coolest larvae are probably caterpillars - they're so colorful and fuzzy!Larvae have one important job: eating! They spend most of their time munching on leaves, wood, or whatever other food isaround. All that eating helps them grow bigger and bigger. It's kinda like how you and I went through a major eating phase when we were babies!After getting nice and plump from all that nomming, the larva is ready for the next stage: the pupa or cocoon stage. Different insects do this part differently. Caterpillars form a cool chrysalis that hangs from a branch. Other larvae just make a basic pupa casing around their bodies.Inside the pupa, the insect doesn't just chill - it does something crazy called metamorphosis. That's when its entire body breaks down and rebuilds itself into the adult form! It's like the insect is a superhero going through an intense transformation sequence. Wild, right?Finally, after all that intense reforming, the adult insect emerges from the pupa! Butterflies gracefully unfold their wings, beetles crawl out sporting their shiny new shells, and other insects stretch and get ready for their grown-up lives.As an adult, insects only have a few main goals: finding food, avoiding getting eaten, and reproducing to create the next generation of eggs. Some adult insects we're familiar with are bees, ants, moths, and flies.Adult insects have some neat skills that help them survive. Many can fly using their wings, which lets them zoom around quickly. Others are super strong and can carry objects much heavier than they are. A few types of insects have wacky defenses like shooting smelly spray or playing dead.Once they've mated, the female adult insects get back to laying eggs and restarting the whole life cycle over again. Pretty epic, huh? Insects might be tiny, but they go through some major transformations in their lifetimes!I think my favorite parts are the pupa stage, since it's just so unbelievably bizarre, and the caterpillar larva stage because caterpillars are adorable little eating machines. What stage do you like best?Insect life cycles are so cool and action-packed. I'm just glad I don't have to liquify my body and rebuild it from the inside out - that sounds rough! I'll stick to my regular human life cycle of just steadily growing up year by year.Thanks for reading about the amazing lives of our six-legged friends! Insects might be small, but their life journey is huge. Stay curious, and keep exploring our incredible natural world!篇2The Awesome Life of Insects!Have you ever watched a caterpillar munching on leaves and wondered what it will turn into? Or seen a flutter of colorful wings and tried to follow that butterfly or moth? Insects are some of the coolest little creatures on our planet, and their life cycles are simply amazing!Let me tell you all about how insects grow and change from tiny eggs into adults that can fly, crawl, buzz and do so many neat things. First, we need to learn about the four stages that all insects go through. It's called complete metamorphosis.Stage 1: The EggIt all starts when a mother insect lays her eggs. Insect eggs can be really tiny, like a speck of dust! Or they may be larger, like the size of a seed. The eggs might be laid on a leaf, under bark, in the soil or somewhere else that's safe for baby insects to hatch.Inside each egg is a teeny insect embryo. It doesn't look like much at first, but amazing changes are happening! As it grows, you can start to see different body parts forming. After awhile, the embryo is all ready to begin its life outside the egg.Stage 2: The LarvaWhen an insect first hatches from its egg, it's still just a baby. We call this the larva stage. Insect larvae look super different than the adults of the same species.Some larvae are caterpillars, like the ones that turn into beautiful butterflies and moths. Caterpillars have lots of stubby legs and spend basically all their time eating leaves and growing bigger.Other larvae are maggots, like baby flies and beetles. Maggots are kinda gross looking but they're just doing their maggot thing! They squirm around and munch on rotting plants, animals or other gross stuff.As the larva keeps growing, it sheds its outer skin layer. This is called molting. After molting several times, the larva is finally ready for the next stage of metamorphosis.Stage 3: The PupaWhen it's time, the larva enters the pupa stage. It settles down, hangs upside down, and begins to form a protective outer case called a chrysalis (for butterfly pupae) or cocoon (for moth pupae). Other insects form different pupal casings.Inside this pupa shell, the insect transforms from its larva body into a completely different form. It's one of the mostmiraculous processes in nature! Cells rapidly rearrange themselves through a process called histolysis and histogenesis. Basically, the old larva body breaks down and new adult body parts grow from specialized tissue groups.Once the transformation is complete, all that's left is for the new adult insect to break free from its pupal shell. This can take days or even months depending on the species.Stage 4: The AdultFinally, the new adult insect emerges by splitting open the chrysalis or cocoon. At first, its wings are shriveled and wet, but it pumps body fluid through them to expand and dry them out.And there you have it - the final form of a butterfly, beetle, fly, ant or any other awesome insect! The adult is the reproductive stage, when insects can mate and lay eggs to begin the cycle anew.Adult insects look and behave totally different than their larva forms. Butterflies can migrate thousands of miles. Bees collect nectar and pollinate flowers. Dragonflies masterfully catch prey in mid-air. Each insect has its own unique skills and behaviors in its final mature stage.And then when the adult insect's lifespan ends, the cycle starts all over again as its eggs hatch into the next generation of larvae.I think the metamorphosis of insects is one of the most fascinating things in nature! It's mind-blowing that a chubby little caterpillar can transform into an ethereal butterfly with vibrant wings and the ability to fly. Or that a tiny speck of an egg contains the DNA instructions for building the complex body and capabilities of a ladybug or praying mantis.There are still so many mysteries about how metamorphosis really works at the molecular level. But one thing is for sure - the life cycles of insects are simply amazing! From egg to larva to pupa to adult, the stages these little creatures go through is an inspiring example of the miracles in our natural world.I hope learning about metamorphosis has made you appreciate insects even more. Next time you spot a butterfly or any other insect, remember the incredible journey it went through to get there! Nature is full of wonderful surprises if we just take the time to look closely.篇3The Amazing Life Cycle of InsectsInsects are super cool little creatures that we can find everywhere around us. Have you ever stopped to think about how they grow and change during their lives? Their life cycles are fascinating!Insects start out as tiny eggs. These eggs come in many different shapes and colors. Some are round and smooth, while others have weird markings or spikes all over them. The mama insect lays the eggs in safe places, like on leaves, in the soil, or even inside other insects or animals! Once the eggs hatch, the insect babies come out.But insect babies don't look like their parents at all. They are called larvae (that's the fancy plural word for larva). Larvae are like tiny squishing, wiggling Gummy Bears. Some crawl around on lots of legs, while others don't have legs at all and just wiggle. Caterpillars, maggots and grubs are all different types of larvae.The larvae's number one job is to eat, eat, eat! They munch on leaves, plants, flowers, fruits, wood, soil, poop, and even other insects. They just keep stuffing their mouths, gulping all that food into their tubey bodies. This helps them grow quickly into...bigger larvae! Crazy, right?After getting tubey enough from eating so much, the larva is ready for the next step. It stops munching and finds a cozy spot.Then an amazing thing happens - the larva transforms into a pupa!The pupa is like a sleeping bag or cocoon that the insect builds around itself. Inside this little capsule, the insect isn't sleeping at all. Nope, it's going through metamorphosis - a total body overhaul! It uses up all the food it ate as a larva to rebuild itself into...a adult insect!Finally, after all those changes inside the pupa, the adult insect emerges. Butterflies, ants, bees, flies, beetles, and many others break out of their pupal cases as their final form. The adult looks nothing like the larva at all. It has six legs, antennas, compound eyes, and sometimes wings to fly.As an adult, the insect's main jobs are to find food for itself, escape predators like birds and lizards, and reproduce by laying or fertilizing eggs. Then the cycle starts all over again with new eggs hatching into larvae!Some insects only go through these stages once in a simple life cycle. But others have complicated, incomplete metamorphosis with extra molting stages in between. No matter how the cycle goes, all insects transform from tiny eggs into hungry larvae, then mighty adults ready to make new generations.The next time you see a bug, think about the incredible journey it went through to get to that form. From a tiny egg, to a wriggly larva survival machine, to a jewel-like pupa, to the final flying, crawling, buzzing insect - what an amazing life cycle! Insects rock!篇4The Amazing Life Cycle of InsectsInsects are so cool! There are over a million different kinds of insects all over the world. They come in all different shapes, sizes and colors. Some can fly, some can jump really high, and some are just plain weird looking. But do you know how they grow and change through their life? It's actually an amazing process called the life cycle.Most insects have four distinct stages in their life cycle – the egg, the larva, the pupa, and the adult stage. It starts off when the adult female lays eggs. Insect eggs can be really tiny, like a speck of dust, or bigger like the size of a pea. The eggs can be laid singly or in huge clusters, sometimes numbering in the hundreds or even thousands!After some time, the eggs hatch into larvae. Larvae are like baby insects, but they look completely different from the adultform. Caterpillars, maggots and grubs are all examples of larvae. This is the eating stage where the larvae just munch away continuously, growing bigger and bigger.All that eating helps them store up lots of energy for the next stage. This is when the larvae go through an amazing transformation called metamorphosis. They shed their outer skin and transform into a pupa. The pupa is like a little capsule with no mouth or eyes. It just hangs out, not eating or moving at all. But inside is where all the magic happens!The pupa is reorganizing and rearranging its body parts to form the adult insect inside. Arms, legs, wings and all the features of the adult develop within the pupa case. After a few days, weeks or even months, the pupal case cracks open and out emerges the adult insect. Isn't that so cool?Not all insects go through the pupal stage though. Some just shed their skin several times and keep growing until they become adults. These are called incomplete metamorphosis insects, like grasshoppers and dragonflies. But most insects like butterflies, beetles, ants and flies go through the complete metamorphosis of egg, larva, pupa and adult.My favorite insect life cycle is definitely the butterfly! The caterpillar hatches from a tiny egg and eats leaves like there's notomorrow. Then it forms a pupa called a chrysalis that looks like a tiny brown hanging sack. After a while, an adult butterfly with beautiful colors and patterns emerges and takes flight. It's just amazing to watch!insect life cycles aren't just fascinating, but they're really important too. As larvae, insects help break down dead plants and animal matter. The adults pollinate flowers which allows fruits and vegetables to grow. Some insects like bees even make yummy honey for us. Life on earth wouldn't be the same without insects and their incredible life cycles.The next time you see a caterpillar munching on leaves or a fly buzzing around, think about the amazing changes it went through to become that adult insect. Insects are the little recyclers and helpers of nature going through their life cycle stages right before our eyes. Pretty cool, right? Nature is just full of awesome surprises!篇5The Amazing Life of InsectsHey there! Today I'm going to tell you all about the really cool life cycles of insects. It's so awesome how they grow andchange from tiny eggs into flying, crawling critters. Let me take you through the journey!It all starts with the egg stage. Lady insects lay lots of tiny eggs, sometimes in cool patterns or protected spots. The eggs are so small, you might not even notice them at first. But inside each one, a teeny tiny baby insect is growing! After a while, the eggs hatch and out comes the larva.Now, larvae can look pretty weird. Some are like squishy worms with lots of legs, while others are kinda like aliens with big chomping mouths. Caterpillars are larvae too - they're the baby versions of butterflies and moths. The larva's main jobs are to eat a ton to grow big and strong, and to avoid getting eaten by hungry birds or other predators.As the larva keeps munching away, it grows and grows until one day, kazam! It goes through an amazing transformation called metamorphosis. It stops eating and gets all sleepy, wrapping up in a cozy little case or chrysalis. Inside, its body is changing in the trippiest way, rearranging into the form of the adult insect it will become.After metamorphosis is complete, the adult insect emerges from its chrysalis, pumping fluid into its wings and body to unfurl them. Tadah! That chunky caterpillar is now a beautiful butterfly,that gross maggot is a house fly, that bizarre grub is a slick beetle. So rad!As an adult, the insect's main drive is to mate and reproduce, spreading its genes to a new generation. Lady insects lay more eggs after finding the perfect spots, using cool strategies like emitting scents or doing little dances to attract mates. Then the cycle starts all over again!Some insects only live for a few weeks as adults before dying, like mayflies who hatch, mate, lay eggs and perish all in one day. Other insects like beetles, ants or termites live for years, with queens laying literally millions of eggs in their lifetimes. No matter how long they live, all insects go through that wild egg, larva, metamorphosis, adult cycle.There are still things even smart scientists don't understand about how exactly these changes happen inside the chrysalis. But one thing's for sure - the process of an insect's life is totally amazing! From tiny eggs to larval eating machines to the final winged form, insects transform in some of the weirdest and most wonderful ways in nature. I hope you've learned some new stuff about our six-legged friends today. Stay curious!。
WORMS：
Highly distributed sensors may be needed to detect topological worms
Target Discovery : Passive Worms
A computer worm is a program that selfpropagates across a network exploiting security or policy flaws.
A computer virus requires some sort of user action to abet their propagation
A passive worm does not seek out victim machines. Instead, it either waits for potential victims to contact the worm or rely on user behavior to discover new targets
Permutation scanning
a worm can detect that a particular target is already infected
all worms share a common pseudo random permutation of the IP address space
Permutation Scanning
Random scanning is inefficient :
many addresses are probed multiple times
【课外阅读】EarlyBirdsMisstheWorms(早出生的小鸟会没有毛毛虫可吃)
Early Birds Miss the Worms(早出生的小鸟会没有毛毛虫可吃）抚养后代需要花费很多的时间，耗费很多的能量。
对于生物来说，如果没有足够的食物是一件非常危险的事情。
经过长期的研究发现：如果大自然不合作的话，亲代对后代的抚养可能会成为空话。
这片文章中揭示：全球气候变暖可能会导致某些鸟类灭绝，因为在食物丰富，可以养活后代之前，这些鸟已经结束了抚养后代的任务。
Climate casualties. Changing climates may cause blue tits to breed out of sync with their food source.CREDIT: GEORGE MCCARTHY/CORBIS自从80年代，法国蒙彼利埃市功能和进化生态研究中心的进化生态学家Jacques Blondel 就开始研究生活在橡树林中的一种叫做蓝山雀的小鸟。
他选择了两个研究地点，一个是在他的研究所附近的树林中，另一个是在125公里外的科西嘉岛上。
在这两个地方，蓝山雀选择不同的生境作为繁殖场所。
在科西嘉岛上，小山雀选择常绿的橡树林作为繁殖地，而在蒙彼利埃市小山雀则选择落叶的橡树林作为繁殖场所。
然而，现在仍有很多生活在大陆上的鸟类，都像生活在科西嘉岛上的山雀一样，选择常绿橡树林筑巢。
大约在四年前，Blondel 和Donald Thomas （加拿大的生理生态学家）决定进一步追踪小山雀的鸟的活动情况。
研究发现：如果让蒙彼利埃市的山雀在常绿橡树林中抚养后代，那它需要的能量是科西嘉岛上山雀抚养后代所需能量的两倍。
原因是：蒙彼利埃市的小鸟繁殖的时间不合适。
Thomas说：科西嘉岛上的蓝山雀在六月份繁殖，这只正是新叶刚刚长出来的时候，而嚼食树叶的毛毛虫的数量也是最多的。
在大陆上，大多数的鸟类要比科西嘉岛上的山雀提早3个星期繁殖，因为在大陆，落叶橡树发芽的时间较早，所以毛毛虫数量丰富的时间也比较早。
WormholesandaHoneyfarmAutomaticallyDetectingNovel
Wormhole
IP: .dd
• Niels Provos suggested: Use honeyd as a first pass filter
– Completes the illusion that a honeypot exists at every wormhole location
Decision (Hypothesis)
Feed Forward
Action (Test)
Unfolding Interaction
With Environment
Note how orientation shapes observation, shapes decision, shapes action, and in turn is shaped by the feedback and other phenomena coming into our sensing or observing window.
Wormholes and a Honeyfarm:
Automatically Detecting Novel Worms
(and other random stuff)
Wormholes and a Honeyfarm: Automatically Detecting New Worms
Nicholas Weaver
UC Berkeley ICIR
Vern Paxson
ICIR
Stuart Staniford
Silicon Defense
1
Problem: Automatically
Detecting New Worms
Wormholes and a Honeyfarm: Automatically Detecting Novel Worms
简单描述蝴蝶的生长过程和特征英语作文
简单描述蝴蝶的生长过程和特征英语作文全文共5篇示例，供读者参考篇1The Amazing Life of ButterfliesButterflies are one of the most beautiful and amazing creatures on Earth! They are insects that go through an incredible change called metamorphosis. This means they look completely different when they are first born compared to when they become adults.It all starts when a butterfly lays her eggs on a leaf or stem of a plant. The eggs are really tiny, about the size of a pinhead. They can be different colors like white, yellow, green or red. The mom butterfly is very careful to lay her eggs on a plant that the babies (called caterpillars) will be able to eat when they hatch.After a little while, the eggs hatch and out come the caterpillars! Caterpillars don't look anything like butterflies. They are long, fat, and wiggly with lots of legs. Their bodies are made up of different segments. Some caterpillars are green and blend in with the leaves they eat. Others can be bright and colorful as awarning that they don't taste good if other animals try to eat them.The first thing a caterpillar does after being born is eat and eat and eat! They have huge appetites and just keep munching on leaves all day long. As they eat, they grow bigger and bigger. Pretty soon, their skin gets too tight and they molt, shedding their outer skin like you take off your shirt. Underneath is a new, bigger skin that lets them keep growing.Caterpillars do nothing but eat for 2-4 weeks until one day they stop eating and start looking for a safe place to rest. When they find the perfect spot, the caterpillar attaches itself to a stem or leaf and hangs upside down in a funny looking J-shape. It almost looks like the caterpillar is taking a nap!But the caterpillar isn't sleeping at all. It is getting ready for one of the most amazing things that happens in nature. Its body begins releasing enzymes that digests everything inside until the caterpillar basically turns into a thick liquid called caterpillar soup! This liquid inside the caterpillar's old skin reshapes itself into a beautiful chrysalis or pupa.The chrysalis is like a safe little house where the caterpillar soup undergoes an incredible transformation over the next 1-2 weeks into a butterfly. If you could see inside, you would see thecaterpillar soup using instructions locked away in its cells to reorganize into eyes, wings, legs and all the other parts a butterfly needs. This process of changing completely from one thing into another is called metamorphosis.When the time is just right, a cracking sound comes from the chrysalis as the newly formed butterfly starts wiggling out. Its wings are all soft and crumpled at first. The butterfly keeps pushing its way out until finally it hangs upside down from the empty chrysalis. Over the next few hours, fluid is pumped from the body into the wings to make them unfurl, stretch out and dry into their full beautiful shape.Now that it has become a butterfly at last, it will only live for 2 weeks to a month. First it must find a mate to reproduce with. The males often have much brighter colors to help attract females. When they sense a female is close by, they perform a special fluttering mating dance up and down in the air!Once they mate successfully, the female will fly around looking for the perfect plants to start the cycle all over again by laying her eggs. Butterflies use their super long tongues to drink nectar from flowers, which gives them energy. Flowers and butterflies need each other – one for the nectar, and the otherfor pollination as the sticky pollen sticks to the butterflies and gets carried from flower to flower.An adult butterfly's life may be short, but what an amazing journey! From a tiny speck of an egg, to a hungry leaf-eating caterpillar, to a protective pupa, and finally emerging as a beautiful winged insect floating from flower to flower. The more you learn about butterflies, the more fascinating and incredible they become!篇2The Amazing Life of ButterfliesHi everyone! Today I want to tell you all about one of my favorite insects - butterflies! Butterflies are so pretty and colorful. They flutter around gardens and fields on their delicate wings. But did you know that butterflies start out looking totally different from how they end up?Butterflies have an amazing life cycle with four distinct stages. It all begins as a tiny egg laid on a plant by a mother butterfly. The egg is really small, about the size of a pinhead. It looks kind of like a raindrop or a tiny bead.After a little while, the egg hatches and out comes a caterpillar or larva. The caterpillar doesn't look anything like abutterfly at this stage! It's a chubby little worm-like creature with lots of little legs. All caterpillars can do is eat and grow bigger. In fact, that's what they spend most of their time doing at this stage!Caterpillars love munching on leaves and will eat the plant that the mother butterfly laid her egg on. Different types of caterpillars like to eat different types of plants. Some eat vegetable plants while others prefer trees or flowers. They just chomp away all day, getting bigger and fatter!As the caterpillar keeps growing, it has to shed its outermost layer of skin called the exoskeleton. This happens multiple times while the caterpillar is getting bigger. After doing this for the last time, the caterpillar is finally ready to move on to the next stage of its life cycle.Now here's where things get really wild! The caterpillar looks for a safe spot and uses silk to attach itself to a branch or surface. Then an amazing transformation happens - the caterpillar's outer skin splits apart to reveal a hard protective case underneath called a chrysalis or pupa. Inside this chrysalis, the caterpillar is rapidly changing into a butterfly through a process called metamorphosis.The chrysalis is like a little house where the caterpillar goes through an incredible makeover. Its body is basically turning to mush on the inside! But at the same time, it is using that mush to construct new body parts like wings, legs, and antennae. Wild, right?After spending weeks or months inside as a chrysalis, a beautiful butterfly emerges! It has to hang upside down for a while so its wings can unfurl and dry out before it can fly away. When the butterfly first comes out, its wings are all crumpled up. But after resting, the colorful butterfly stretches out its large, delicate wings and takes its first flight!Adult butterflies have some really cool characteristics that help them survive in nature. Their wings are covered in tiny scales that create intricate patterns and shades of color. The patterns help some butterflies blend in with their surroundings to hide from predators. Other butterflies have bright colors that warn enemies they are poisonous if eaten.Have you ever noticed how butterflies feed on flowers? They have a long, curled up proboscis (kind of like a straw) that can unfurl and extend into flowers to slurp up nectar. Butterflies need nectar for energy to power their flight. In return, butterflieshelp pollinate the flowers, which allows plants to make seeds and reproduce.The biggest threat to butterflies is habitat loss. Many butterflies depend on specific plants for laying eggs and as food for their caterpillars. When forests, fields, and gardens get paved over or sprayed with pesticides, it destroys the homes and food sources that butterflies need to survive.Some people even raise and study butterflies, called butterfly farming or ranching. It's a great way to learn about the life cycle up close while also helping boost butterfly populations. You can order caterpillars or chrysalises in the mail and build a special habitat for them. Then you get to see them transform into beautiful butterflies before your eyes!I hope you found the incredible life story of butterflies as fascinating as I do. Next time you see one gracefully fluttering by, remember the long journey it went through to get its wings. From a tiny speck of an egg, to a munching caterpillar, to a篇3The Amazing Life of ButterfliesHi friends! Today I want to tell you all about one of the most wonderful creatures in nature - butterflies! Butterflies are sopretty and delicate, with their vibrant colors and beautiful wings. But did you know that butterflies go through an incredible transformation during their life? It's one of the most amazing things in the whole world!Butterflies have a very special life cycle called'metamorphosis'. This is a fancy word that means they completely change their body and form as they grow up. It happens in four different stages.The first stage is the egg. A butterfly starts off as just a tiny, tiny egg laid on a leaf by a mama butterfly. The egg looks like a little raindrop or dewdrop on the leaf. Inside the egg, a tiny caterpillar (called a larva) is growing!Once the caterpillar is ready, it hatches out of the egg. This brings us to the second stage, which is the larva or caterpillar stage. The caterpillar doesn't look anything like the beautiful butterfly it will one day become. Caterpillars are kind of chubby and wrinkly, with lots of little legs.But caterpillars are eating machines! They spend basically all their time munching on leaves to grow big and strong. Some caterpillars can eat an entire plant all by themselves! As they eat, they grow and grow, getting bigger and bigger. Soon they don'teven fit in their own skin anymore, kind of like when you outgrow your clothes.So here's what the caterpillar does - it molts! That means it sheds its outer skin like a snake sheds its skin. After molting a few times and getting bigger each time, the caterpillar is finally ready for the next stage.The third stage is the pupa stage, and this is when that crazy metamorphosis really happens! The caterpillar attaches itself to a twig or leaf and starts spinning a little cozy capsule all around itself. This capsule is called a chrysalis. Inside the chrysalis, the caterpillar is rapidly changing and reforming into a butterfly!While snuggled up in the chrysalis, the caterpillar is using up all the food it ate and stored as a caterpillar. Its body is breaking down and reforming itself into the beautiful butterfly body we all recognize - with two big eyes, two antennae, three body segments, six legs, and four brilliant wings.After a few weeks to a couple months of this incredible transformation happening in the chrysalis, the fourth and final stage begins. A beautiful adult butterfly emerges and climbs out of the chrysalis! At first its wings are all crumpled and wet. But the butterfly pumps fluids from its body into the wings, unfurling and drying them.And then the butterfly is ready to take flight on those magnificent wings for the first time! Isn't that just the coolest thing you've ever heard?But butterflies don't have much time to enjoy being a butterfly after all that work of metamorphosis. Most butterflies only live 2-4 weeks as adults. Their main goals are to find a mate, and for females to lay eggs to start the cycle all over again.Butterflies have some unique traits that help them survive in this short adult stage. Their wings are covered in tiny scales that give them those vibrant colors. The scales also help soak up warmth from the sun, which butterflies need for energy to fly.They taste with their feet, and can even taste with the sensors on their legs when they are walking around! Their compound eyes give them an incredibly wide field of vision to watch out for predators. And their long proboscis (like a tongue) allows them to sip nectar from flowers.There are so many amazing kinds of butterflies all around the world. Some migrate incredibly long distances in their lifetimes. Others are great camouflage artists that can blend into leaves and bark. And some species are absolutely gigantic compared to others!My favorite butterflies are the monarchs. They are bright orange with black stripes and white spots. Monarchs are super resilient and migrate thousands of miles from the United States and Canada all the way to Mexico for the winter! How wild is that?I just think the entire life story of butterflies is one of the most fascinating, unbelievable, and straight up cool things in the natural world. From a tiny egg, to a munching caterpillar, to a crysalis, and then finally emerging as a beautiful, graceful butterfly - what an journey!I hope you learned something new and enjoyed reading about the epic life of butterflies. Next time you see one, remember the amazing metamorphosis it went through to get those gorgeous wings. Butterflies are living proof that incredible changes can happen when you start out as something completely different!篇4Here's an essay in English describing the life cycle and characteristics of butterflies, written in a simple style suitable for elementary school students (around 2000 words):The Amazing Life of ButterfliesButterflies are one of the most beautiful and fascinating creatures on our planet. With their vibrant colors, delicate wings, and graceful movements, they bring joy and wonder to people of all ages. But do you know how these incredible insects go through life? Let me tell you the amazing story of the butterfly!It all starts with a tiny egg. A female butterfly lays her eggs on the leaves of specific plants, called host plants. These eggs are very small, sometimes even smaller than a grain of rice! After a few days or weeks, a teeny-tiny caterpillar hatches from the egg. This is just the beginning of the butterfly's incredible journey.The Hungry CaterpillarWhen the caterpillar first comes out of the egg, it is super hungry! It starts munching on the leaves of the host plant right away. As it eats and eats, the caterpillar grows bigger and bigger. But something else happens too – it sheds its skin! Yes, you heard me right. The caterpillar's skin becomes too tight, so it wiggles out of it and gets a brand new, bigger skin. This process is called molting, and some caterpillars go through it four or five times before they are fully grown.During this caterpillar stage, they have an important job –eating as much as possible! They need to store up lots of energy for the next part of their life cycle. Some caterpillars are sohungry that they can eat an entire plant before they're done growing!The Amazing TransformationAfter weeks of non-stop eating, the caterpillar is finally ready for the next step – turning into a chrysalis (or pupa, if you're talking about moths). The caterpillar attaches itself to a twig or a leaf with a silky material and sheds its skin one last time. But this time, something magical happens! The outer layer hardens into a protective casing called a chrysalis.Inside this cozy little home, the caterpillar starts to transform into a butterfly. It's like a superhero getting a whole new body and costume! The caterpillar's body breaks down into a soupy mixture, and then it rebuilds itself into a butterfly, complete with beautiful wings, a long tongue for sipping nectar, and six legs.After a few weeks or months (depending on the butterfly species), the chrysalis cracks open, and out comes a brand new butterfly! At first, its wings are all crumpled up, but the butterfly pumps fluids into them, and they slowly unfold and dry, becoming the beautiful, delicate wings we all know and love.The Life of a ButterflyOnce the butterfly emerges from the chrysalis, its life is quite different from the caterpillar stage. Instead of munching on leaves, butterflies sip nectar from flowers using their long, coiled tongues. They flit from flower to flower, pollinating plants as they go – which means they help plants make new seeds and fruits.Butterflies are also very important food sources for other animals like birds, bats, and even some small mammals. Their bright colors and patterns help them blend in with their surroundings or warn predators that they are poisonous (if they've eaten toxic plants as caterpillars).One of the most amazing things about butterflies is their ability to migrate long distances. Some species, like the Monarch butterfly, can travel thousands of miles to find warmer climates during winter! They use the sun, Earth's magnetic field, and even their sense of smell to navigate these incredible journeys.Butterflies usually live for just a few weeks or months as adults, but in that short time, they mate and lay eggs to start the incredible life cycle all over again.Incredible InsectsButterflies are truly incredible insects. From their amazing transformation to their important role in nature, they never cease to amaze us. Next time you see a butterfly fluttering by, remember the journey it went through to get those beautiful wings. And who knows? Maybe you'll feel a little bit of magic too!篇5The Amazing Life of a ButterflyHi friends! Today I want to tell you all about one of the most incredible creatures on Earth - the butterfly! Butterflies are beautiful insects with big colorful wings that flutter around looking for nectar from flowers. But do you know how they grow up to become those pretty insects we see flying in the garden? It's an amazing process called the life cycle!A butterfly starts off as a very tiny egg laid on a leaf by a butterfly mom. The egg looks like a tiny drop of water or a small bead. After a little while, the egg hatches and out comes a tiny, funny looking caterpillar or larva. Baby caterpillars are sometimes called caterpillars but they don't have any legs yet! They are just these little worm-like things.The caterpillar's main job is to eat and eat and eat some more! They chomp down on leaves from the plant the egg was laid on. As they eat, the caterpillar grows bigger and bigger and bigger. They actually shed their skin or molt several times as they outgrow their old skin. Crazy right?After a few weeks of nonstop eating, the caterpillar is fully grown. That's when the really cool part happens - it forms a pupa or chrysalis! The caterpillar attaches itself to a branch or stem and sheds its skin one last time. Underneath, there is a hard protective layer called a chrysalis. Inside this chrysalis, the caterpillar is going through an incredible change called metamorphosis.While inside the chrysalis, the caterpillar is turning into a butterfly! Its body is basically melting and reforming into the body parts of a butterfly. It gets a proboscis or a long tongue for drinking nectar, antennae, wings, and six legs. After a couple of weeks, the chrysalis cracks open and out emerges the beautiful butterfly!When the butterfly first comes out, its wings are all crumpled up. It has to pump fluids into them to unfurl and stretch them out fully. Once the wings are dried out and ready, the butterflytakes its very first flight! How amazing is that transformation from a little caterpillar to a stunning butterfly?Now let's talk a bit more about what butterflies look like. They have four wings that are covered in thousands of tiny scales. The scales are made of protein and give the wings their vibrant colors and patterns. Different butterfly species have totally unique and diverse wing patterns and colors. Some mimic leaves or bark to camouflage themselves from predators.In the middle of the butterfly's body is the thorax where the legs and wings are attached. The butterfly has six jointed legs that help it crawl around and perch on flowers. At the front of the butterfly is its head with its two antennae and a proboscis or tongue that uncoils for drinking nectar and water.Butterflies use their long tongues to sip sweet nectar from flowers which provides them energy for flying. While feeding on flowers, butterflies also help pollinate plants by spreading pollen between different flowers. Some species migrate incredible distances traveling between regions where they can breed, lay eggs, feed, and live.Butterflies make the world more beautiful with their graceful flitting around gardens, fields, and forests. I hope you learned just how incredible these insects are by going through such anunbelievable life cycle and transformation. From an egg to caterpillar to pupa and finally emerging as a stunning butterfly - it's one of the most amazing processes in nature! Next time you see a butterfly, remember all the different stages it went through to become that colorful creature. Pretty cool, isn't it?。
我的同桌是条虫英语作文
我的同桌是条虫英语作文My desk mate is a worm. It's not the most conventional choice, but hey, who am I to judge? At first, I was a bit freaked out, but now I've come to appreciate its quiet company. It's always there, munching on my pencil shavings or curled up in a little ball. 。
I've named it Squiggles, because, well, it squiggles around a lot. It's kind of cute in its own weird way. Sometimes I catch myself talking to it, telling it about my day or asking for its opinion on things. I know it can't understand me, but it's nice to have someone (or something) to listen. 。
Squiggles has become a bit of a mascot in our class. Everyone knows about my unusual desk mate and some even come over to say hi. It's funny how something so small and insignificant can bring people together. Who would have thought a worm could be so popular?I've even started bringing in little treats for Squiggles, like bits of apple or carrot. It's funny to watch it wriggle with excitement when I offer it something tasty. I never thought I'd be feeding a worm, but here we are. Life is full of surprises, isn't it?Overall, having a worm as a desk mate has been an unexpected adventure. It may not be what I imagined when I first walked into class, but I wouldn't change it for the world. Squiggles may be just a worm, but to me, it's a friend. And that's all that really matters.。
介绍一个来自大自然的发明英语作文
介绍一个来自大自然的发明英语作文全文共5篇示例，供读者参考篇1Nature's Amazing Sticky StuffHi there! Today I'm going to tell you all about one of the coolest things I've ever learned about from nature. It's this really neat sticky stuff that some animals use. Get ready, because this sticky invention is going to blow your mind!You've probably seen spiders and their webs before, right? Those webs are made out of a super sticky material called silk. Silk comes out of special body parts on the spider called spinnerets. It starts out as a liquid, but then it dries into a solid thread that the spider uses to make its web.Spider silk is honestly just the craziest thing. It's way stronger than any man-made material we've invented so far. A strand of spider silk that's as thin as a pencil could stop a Boeing 747 jet from taking off! At the same time, it's also incredibly stretchy and flexible. It can stretch out to double its normal size without breaking. That's seriously strong stuff.But wait, it gets even crazier! Some types of spider silk are actually stronger than steel, weight for weight. And get this - some spider silks are even tougher and stronger than Kevlar, the material they use to make bullet-proof vests! Isn't that just mind-blowing? Spiders are making these incredibly tough materials right out of their own bodies.Of course, spiders don't just use their silk to make webs for catching food. Some spiders also use it to protect their eggs or make cozy little silk blankets for themselves. And certain types of spiders can even use their silk to sail across water or glide through the air! They make a little silk parachute and ride the wind currents. How crazy is that?Now you're probably wondering - why is spider silk so insanely strong? Well, the secret is in how it's made up of special proteins folded up in a very specific way. When the silk dries out, those protein molecules form super tough crystals linked together by lots of hydrogen bonds. That's what gives spider silk its crazy strength.But despite how amazing spider silk is, scientists have had a really tough time trying to recreate it themselves in the lab. You see, the way spiders spin their silk is a very long and complicated process with lots of steps. First they have to produce the silkproteins, then carefully stretch them out into the right shape, and then finally allow them to crystallize into that solid form. It's not easy to copy nature!Still, people have been trying to mass-produce artificial spider silk for years now. It would be incredibly useful for all sorts of things like making super tough ropes, seatbelts, parachutes, and even body armor. Some companies have managed to produce little bits here and there, but no one has quite cracked the code on making huge amounts of it yet.Personally, I think spider silk is just the most amazing material ever. It makes me realize how incredible nature can be sometimes. Those little spiders are basically making liquid protein turn into one of the toughest materials on the planet, using nothing but their own bodies. I don't know about you, but I find that totally mind-blowing!We humans tend to think we're so smart with all ourman-made inventions and technologies. But when you learn about something as awesome as spider silk, it makes you realize that nature got there first. Those spiders have been making better stuff than any of our kevlar or carbon fiber for millions and millions of years. We've still got a lot to learn from the natural world!So there you have it - my introduction to one of nature's greatest material inventions. The next time you see a spider web, remember - that sticky silk is way tougher than it looks. Those spiders are making some seriously strong stuff, using nothing but protein from their own bodies. Pretty cool, huh? Nature never fails to amaze me with its incredible inventions!篇2Nature's Amazing Dandelion InventionHave you ever blown on a dandelion flower and watched all the little fluffy pieces float away? Those fuzzy pieces are actually called seeds and they get carried by the wind to grow new dandelion plants far away. Isn't that super cool? Dandelions invented the most genius way to spread their seeds all over the place using just the air! Let me tell you all about it.Dandelions are these bright yellow flowers that grow really low to the ground. Their petals form a circle around a big fuzzy middle part. That middle part is made up of hundreds of tiny seeds attached to fluffy white parachutes called pappus. Pappus means "old man's hair" in Greek because it kind of looks like fuzzy gray hair!When the dandelion flower first blooms, the petals open up and the middle is a solid yellow ball. That's when bees come and collect some of the yellow pollen to make honey. After a few days, the petals shrink away and the yellow middle part starts to get fluffier and fluffier as all the parachutes grow out.Finally, the puffy white seed head is ready to release its seeds into the wind. A single dandelion flower can have over 200 seeds! All it takes is a little breeze or a child blowing on the white puffball and those parachutes detach and get swept up into the air currents. The parachutes are designed to catch the wind and the seeds dangle below, just waiting to be dropped off somewhere new.The really crazy thing is that air currents can carry dandelion seeds over half a mile away! So one dandelion plant has the power to populate a huge area with new plants. And they don't get tired of spreading either – each dandelion flower can produce several puffy white seed heads one after another all season long. Talk about productive!Dandelion seeds are built to travel far and wide, but their parachutes are also made to stick the landing. You know that tuft of fuzzy threads at the top of the parachute? Those strands actually produce a natural glue that helps the seeds adhere tothe ground wherever they land so they don't just blow away again. Once anchored, the seeds can soak up rain and start sprouting their first tiny leaves and roots.Not only are dandelions expert at spreading themselves around, but they are also really hardy and can grow just about anywhere. Their roots can crack through concrete and their leaves are filled with a milky liquid that insects don't like to eat. Dandelions will keep on coming back year after year no matter what!In my opinion, nature must have spent a ton of time designing dandelions to be such efficient seed spreaders. It's truly an amazing plant invention. With just some sun, wind, and a little bit of fluff, dandelions populate entire fields with their sunny flowers. Next time you see one, you can appreciate how genius and intricate the natural world really is. Those fuzzy little parachutes are actually a sophisticated dispersal system millions of years in the making! Pretty awesome for a so-called weed, right?篇3Here's an essay introducing an invention from nature, written in a style suitable for elementary school students, in English with a length of around 2000 words.Nature's Wonders: The Amazing Spider WebHave you ever looked closely at a spider web? It's one of nature's coolest inventions! Spider webs are made of thin, sticky threads called silk. Spiders can spin this silk to create amazing webs that are strong, stretchy, and sticky. Let me tell you more about these awesome spider creations!Spiders are like little engineers and architects. They carefully plan and build their webs to catch insects for food. Different spiders make different kinds of webs, but they all follow the same basic steps. First, the spider finds a good spot to build its web, like between two trees or in a corner of your house. Then, it starts spinning a non-sticky thread called the frame thread. This helps map out the shape of the web.Next comes the real magic! The spider makes a sticky spiral thread using a special liquid from its body called spider silk. This silk is super strong and can stretch a lot without breaking. It's even stronger than steel! As the spider moves in a spiral, it leaves behind this sticky silk thread. Insects get caught on the sticky spiral when they fly into the web.But spiders don't just spin random webs. Each kind of spider has its own web design that works best for catching certain types of insects. For example, the orb-weaver spider makes a classic spiral web that's perfect for trapping flying insects like flies and mosquitoes. The funnel-web spider builds a flat, horizontal web with a funnel-shaped entrance to catch crawling insects like beetles and ants.Spiders are true artists when it comes to web-building. They use different techniques to make their webs even stronger and more effective. Some spiders add extra silk threads called guy lines to support their webs. Others make decorative patterns or zigzag shapes in the middle of their webs to attract more insects.Imagine if humans could create something as amazing as a spider web! We'd need strong, stretchy materials like spider silk. Scientists are actually studying spider silk to see if they can use it to make things like bullet-proof vests, artificial muscles, and even bridges! Spider silk is lightweight, yet tougher than steel or Kevlar. It's also biodegradable, so it's environmentally friendly.Spiders have to constantly repair and rebuild their webs because they get damaged or destroyed. But they don't mind at all! They just get right back to work, spinning new webs withtheir endless supply of silk. Some spiders can even spin a whole new web in just one hour!So the next time you see a spider web, don't just walk past it. Stop and take a closer look at this incredible natural invention. Admire the intricate patterns, the perfect spirals, and the amazing stickiness of the silk threads. You might even see the clever spider architect hard at work, spinning its masterpiece!Spider webs are proof that nature is the greatest inventor of all. These tiny creatures can create Works of art that put human architecture and engineering to shame. Who knows what other secrets and wonders are hidden in the natural world around us? All we have to do is open our eyes and look closely. Nature's inventions are everywhere, just waiting to be discovered and appreciated.篇4Nature's Amazing Invention: The Spider WebHi there! Today I want to tell you all about one of my favorite things from nature - the spider web! Spider webs are so cool and the spiders that make them are super neat little creatures. Let me explain why I think spider webs are an amazing invention.First off, spider webs are incredibly strong for something so tiny and delicate looking. The silk that spiders use to make their webs is stronger than steel! Can you believe that? It's made from just tiny strands of protein that the spider produces in its body. Spiders can use this silk to construct elaborate webs that can catch prey much bigger than themselves, like flies, bees, and even small birds or bats. The web has to be really sturdy to handle that.Another amazing thing about spider webs is how sticky they are. The silk has tiny droplets along it that are super sticky and good at trapping anything that flies into the web. But get this - the silk itself isn't sticky at all! Isn't that wild? The stickiness comes from a special coating that the spider puts on only certain parts of the web. That way, the spider can walk all over its own web without getting stuck. So clever!Speaking of clever, do you know how spiders construct their webs? It's an incredible process that they are just born knowing how to do. First, the spider has to pick the perfect spot for its web and make a frame out of non-sticky silk. Then it starts adding the sticky capture spiral, going round and round in a spiral pattern from the outside in. The spider uses its back legs tohelp lay down the sticky silk and its front legs to carefully walk on the non-sticky parts.What's really mind-blowing is that spiders can sense the vibrations on their webs, sort of like hearing with their feet! That allows them to immediately detect if an insect or something else gets caught in the web. Then the spider races over to wrap it up in more silk before paralyzing it with venom so it can eat later. The web itself acts like a built-in security system for the spider! How awesome is that?As if that's not enough, many spiders rebuild their webs every single day. All that intricate construction work and they just tear it all down in the morning and start fresh. Though I guess for them it's like making their bed every day. Their web is their home after all. Some larger spider species can leave their webs up for a few days, but smaller spiders need to rebuild constantly for maximum stickiness and to repair any damage.Here's another crazy spider web fact for you: did you know that the very first web a baby spider builds is a mini one, perfectly formed? How does a tiny baby know how to construct something so detailed and mathematical right from the start? Scientists think it's encoded into the spider's DNA, built into its genes. Baby spiders can somehow tap into millions of years ofevolution, allowing them to produce one of nature's most amazing architectural creations without any instruction at all. Isn't that incredible?Of course, spider webs aren't just marvels of nature, they're also super useful for humans too. Spider silk is an amazing material that people have used for all kinds of things like making crosshairs in microscopes and telescopes. Some people are even trying to produce artificial spider silk that could be used for parachute rappelling lines, biodegradable bottles, and even bulletproof vests! Spider silk is stronger than Kevlar, the material used in bulletproof vests today. So in the future, soldiers might be wearing body armor made of spider web proteins. How wild is that?But you don't need to look to humans to see how useful and amazing spider webs are. Just look around you next time you're playing outside. You'll find these intricate, geometric constructions everywhere, each one built by a tiny eight-legged architect following an ancient blueprint encoded into its very being. Spider webs are everywhere, yet no two are exactly alike. Each one is a unique masterpiece of nature.So there you have it, my big kid report on one of nature's most mind-blowing inventions - the spider web! I could honestlygo on and on about all the incredible things spiders can do, like the different web designs different species make, or how some spiders can actually take their webs apart and re-use the silk when they move somewhere new. But I'll stop here for now so you can go look for some spider webs yourself and gain a new appreciation for these miniature marvels of nature. Keep your eyes peeled and your mind open, because who knows what other awesome inventions are awaiting us from the natural world?篇5The Amazing Spider WebHi friends! Today I want to tell you all about one of the coolest inventions ever - the spider web! Spiders are totally awesome little creatures that can do something pretty much no other animal can do. They make these incredible web thingies out of silk that comes right out of their bodies! How crazy is that?I'm sure you've all seen spider webs before, maybe with dew drops sparkling on them in the morning sun. Or you might have walked face-first into one while running around outside (yeah, that's no fun!). But have you ever really looked closely at a spiderweb and thought about how amazing it is? Let me break it down for you.First off, the silk that spider webs are made of is super strong stuff. It's actually stronger than steel! Can you believe a tiny little spider can make something tougher than that heavy metal people use to build skyscrapers and cars? The silk is made of proteins that the spider produces in its body. The proteins get all twisted up to form incredibly strong strands.But it's not just strong, spider silk is also really elastic and stretchy. That's why a web can bend and move around in the wind without breaking. The stretchy silk helps absorb any impacts to the web, almost like it's a built-in shock absorber. Genius, right?Another awesome thing about spider webs is how they are made with different types of silk. The spoke parts that radiate out from the center are made with a tough, no-stretch silk. But the spiral capture part is made with really stretchy, sticky silk. This is what lets the web trap insects and bugs for the spider to eat.Speaking of trapping bugs, have you ever noticed that different spider webs look different? There are orb-shaped circular ones, zig-zag shaped ones, funnel-shaped ones, and more. Each type of web is specially designed by different spidersfor catching specific types of prey. Like, the zig-zag shaped ones are made to trap flying insects.But get this - some really smart spiders don't just build any old web. They actually rebuild their webs every night while we're all sleeping! Can you imagine having to reconstruct your bedroom or home every single day? These spiders have got some work ethic.And just when you thought spiders couldn't get any more impressive - their webs are also self-repairing! If a web gets messed up or torn, the spider can actually feel the vibrations through the silk strands. Then it rushes over and rebuilds that section. Boom! Like magic.Okay, okay, I know what you're thinking - "Eww, spiders are so gross and scary though!" Well, let me remind you that we humans have taken inspiration from spiders' awesome skills. Scientists and engineers have studied spider silk to try and copy it and make super tough materials. There are now spider silk proteins being used to make things like bulletproof vests, safety masks, and medical supplies. How cool is that?Some people have even tried to 'farm' spiders to produce silk that can be woven into threads and fabrics. Imagine wearing a shirt or pants made from the same stuff as a spider web! Itwould be super light but also really strong and flexible. You could run and jump in them all day long.But you know, even if we never wear spider silk clothes, I think just the idea of a spider web is totally fascinating. To be able to create something so intricate and useful, all out of stuff from inside your own body? Using different types of silk for different parts? Having it be strong and stretchy at the same time? Self-repairing it every single day? That's just mind-blowing if you ask me.Spiders might be tiny, but they are little geniuses when it comes to engineering, architecture, and materials science all wrapped up in one. Sure, they can be a bit creepy looking. But their skills at web-making are just awe-inspiring. We should all take a page out of the spider's book on how to build something amazing from scratch using just our natural abilities.So next time you see a spider web glistening in the corner of a window or between some branches, don't just brush it off. Really look at the design, the patterns, the geometry. Think about all the hard work and ingenuity that went into it. Give the little spider architect some respect! Because that webby masterpiece you're looking at is one of the greatest natural inventions ever. Hands down, no debate about it!。
wormstabloid
Vermicompost is a term for therich,crumbly,black compost that is created when earthworms eat their way through a pile of organic matter.Castings is just a fancy word for earthworm excretions.Earthworms are often grouped according to their function in the soil:Anecic worms are usually larger worms that build permanent burrows in the soil and come to the surface to pull bits of leaves or other organic matter into their burrows.Epigeic worms live in decaying organic matter,not in the soil.Endogeic worms rarely come to the surface.Some endogeic worms inhabit the rhizosphere,the area immediately around plant roots,where they feed on soil that has been enriched by decaying roots,bacteria,and fungi.Lumbricus terrestris ,the night-crawler,is a large anecic worm with a flattened tail that is great for your soil,but will not survive in a closed compost bin.Eisenia fetida ,the red wiggler or redworm,is a small epigeic worm,three inches long or less,that thrives in compost bins.Some of these worms have yellow bands between their segments,others do not.Aporrectodea caliginosa ,often called a grey worm or a southern worm,is one of the most wide-spread endogeic species.It’s often found in the roots of plants.As its common name indicates,it is a grey or slightly pink worm about two or three inches long.Definitions•Can-O-Worms•Wriggly Wranch•The Worm Factory•Homemade bin—plastic tub •Large-scale bins are also available for schools,restaurants,and institutions.Types of worm bins•Find a cool,sheltered spot(on a porch or in a garage or basement)•Protect worms from extreme temperatures (their ideal temperature range is 60-70 degrees.)•Keep damp but not soggy (never pour water through your bin!)•Start with a layer of peat moss or coir (coconut fiber) bedding •Keep a layer of shredded newspaper or office paper on top •Add crushed eggshells or a pinch of powdered limestone or rock dust to reduce acidity.•Add a small amount of garden soil to provide grit©2004,Amy Stewart,author of The Earth Moved:On the Remarkable Achievements of Earthworms.Worms prefer a healthy,vegan diet!Conditions inthe worm binVegetable scraps Shredded newspaper or office paper Coffee grounds Eggshells Dryer lintPlain pasta or rice Plain breadMeat or bonesFats such as olive oil or salad dressing DairyAnimal feces Very spicy foodsGlossy magazine paper Citrus,hot peppers,onion or garlic (small amounts are OK)What to feed worms What NOT to feed worms W hen you set up your worm bin,start feeding slowly.One pound of worms (about 1,000 worms) can eat up to half a pound of food per day.However,this depends greatly on conditions in the worm bins and how appetizing the food is (worms love melon and banana skins!).Also,finely chopped food is easier for worms to eat than,for instance,a head of lettuce thrown in whole.Putting in more food than the worms can eat might lead to infestations of other pests in the bin.It can also increase the acidity and make the bin smell unpleasant.Over time,you will get to know how much food your worms can take at once.Even an indoor bin could attract a few other critters.Most other bugs are harmless and may,in fact,help to break down the compost so the worms can better digest it.Keeping a tight-fitting lid on your bin and putting your kitchen scraps directly in the bin (as opposed to,for instance,dropping them in a bucket outside and adding them later) will help keep bugs out of your bin.Here are some examples of other bugs you might find in your worm bin:Fruit flies:These tiny creatures are annoying but harmless.Reducing the acidity of your bin and keeping food buried under a layer of news-paper will help discourage them.Ants:Ants are great decomposers.However,if you don’t want them around,try sprinkling borax around the base of the composter or using store-bought bait.Just be sure the bait is not accessible to worms (and pets and children!).Sow bugs:Also called pill bugs.These are the little hard-shelled bugs that roll up into a ball.They are harmless,but you can pick them out of your bin (a garden spade works great for this) if you don’t want them.Potworms:These are tiny white worms that you might mistake for baby redworms.They are great decomposers and there is no reason to discourage them.Slugs and snails:Yuck! Pick them out with a garden spade and toss them into the street! (or crush them under your foot,or drown them in a bowl of stale beer!)Other critters in the worm binCo m p o s t i n g w i t h E a r t h w o r m s•Most worms live just a few years.•Worms are hermaphroditic:they have both sets of sexual organs and line up head-to-tail to mate.•You will find worm cocoons in your bin from time to time.They are tiny brownish sacs,from which two or three baby worms will emerge•Baby worms are translucent with a red vein running through them.•Some people say a healthy earthworm population will doubleevery sixty days.This is a very optimistic figure! However,in the very best conditions,an initial quantity of 1,000 worms (one pound) will expand to fill a bin within a few years.•There is no such thing as too many worms in a worm bin.The worm population is somewhat self-regulating—it will expand to meet the available food source.However,if you’ve got a bin full of worms,there’s nothing wrong with scooping some out to share with a friend!Life as an EarthwormHarvesting and Using VermicompostAmy Stewart lives in northern California with her husband, two cats, and several thousand worms.She is the author of From the Ground Up: The Story of a First Garden , and the garden columnist and book critic for the North Coast Journal . Her articles appear in a number of magazines and newspa-pers, including Organic Gardening ,Bird Watcher’s Digest , the San Francisco Chronicle , and the San Diego Union-Tribune .WORMS OF ENDEARMENT:Visit what may be the first-ever worm blog. Amy keeps an online diary about her book tour and her life with worms at /Draining the liquidMost composters have some way of draining off liquid from the bottom of the composter.Some bin manufacturers claim that this liquid is a very healthy "compost tea" that makes a great plant fertilizer.Other worm experts think this liquid is too acidic and too full of anaerobic bacteria to be of benefit to most plants.I pour mine into my flower beds and I’ve never seen any problems;but you be the judge.Harvesting castings in a stacking bin systemMost worms will have left the bottom tray that you plan to harvest.If some worms remain,you can put the tray of castings on top of the stack and leave the lid off.The exposure to light may send them diving for cover.Harvesting castings in a single-layer systemOnce your bin starts to get full of castings,start feeding only in one corner of the bin.That will attract worms to that corner and encour-age them to leave the other end of the bin,where you want to har-vest your castings.If,after a few weeks,you still see a lot of worms in the side of the bin without food,you can also place a melon rind or apple core in that area.The worms will be drawn to it and can easily be scooped out and relocated.I keep a garbage can full of finished,aged compost around,so if I add worm castings to that can,I figure a few extra worms can’t do any harms.If you add the worms to your garden,they will only survive if they have a very rich,damp pile of mulch or compost to investigate.Using vermicompostNew studies are starting to show that vermicompost can not only nourish plants,it can also help prevent plant diseases.Add a tea-spoon (or small shovelful) to potted plants or transplanted seedlings.Work it into the soil when you’re planting vegetable beds.Add a little to water and use within 24 hours as compost tea.W ORM R ESOURCESCo m p o s t i n g w i t h E a r t h w o r m s V i c S t e w a r tWorm photos:Amy Stewart – Graphic design: – © 2005,Amy StewartIf you’re just getting started,read:Appelhof,Mary.Worms Eat My Garbage (Flower Press,1997).Nancarrow,Loren and Taylor,Janet Hogan.The Worm Book(Ten Speed Press,1998)For information about large-scale worm projects,read:Payne,Binet.The Worm Cafe:Mid-Scale Vermicomposting of Lunchroom Wastes (Flower Press,1999).Wilson,Eric.Worm Farm Management:Practices,Principles,Procedures (Kangaroo,1999).And the all-time best book about earthworms is:The Formation of Vegetable Mould,Through the Actions of Earthworms,With Observations on their Habits ,by CharlesDarwin.The book was published in 1881.You can find many charming old copies,as well as some more affordable reprints,at ,or ask your favorite used bookstore to help you find one.MagazineWorm DigestPO Box 544,Eugene,OR 97440A quarterly magazine published by a non-profit in Eugene,OR.Their website features a lively worm discussion forum.Includes links to other websites of interest.Publishes The Art of Small-Scale Vermicomposting,a handy reference guide for home composters.Websites and Worm ForumsVery active discussion The website of Mary Applehof,leading worm educator and enthu-siast.Hosts seminars and sells worms,books,videos,and Hosts an online discussion forum for Can-O-Worms users.Also sells worms,bins,books,and other items.The website for Gardeners Supply Company.They sellworm bins and other great gar-den supplies .And of course:In her witty and offbeat style,Amy Stewart shows just how much depends on the humble worm.Kirkus Reviews calls the book “A nifty piece of natural history.Earthworms of the world can stand a little taller.”Available wherever books are sold,or by visiting 。
2010年小学科普英语趣味阅读翻译20110222
ButterfliesA butterfly is a mainly day-flying insect of the order Lepidoptera, the butterflies and moths. Like other holometabolous insects, the butterfly's life cycle consists of four parts, egg, larva, pupa and adult. Most species are diurnal. Butterflies have large, often brightly coloured wings, and conspicuous, fluttering flight. Butterflies comprise the true butterflies (superfamily Papilionoidea), the skippers (superfamily Hesperioidea) and the moth-butterflies (superfamily Hedyloidea). All the many other families within the Lepidoptera are referred to as moths. .蝴蝶蝴蝶是鳞翅目，蝴蝶和飞蛾主要天飞行的昆虫。
像其他holometabolous昆虫，蝴蝶的生命周期由四个部分组成，卵，幼虫，蛹和成虫。
大多数种是日间活动的。
蝴蝶有大，往往色彩鲜艳的翅膀，和突出，飘飘飞行。
包括真正的蝴蝶蝴蝶（家族Papilionoidea）时，船长（家族Hesperioidea）和蛾，蝴蝶（家族Hedyloidea）。
所有许多其他家庭内鳞翅目被称为飞蛾。
科普阅读：Giant Panda大熊猫Giant PandaThe giant panda (Ailuropoda melanoleuca "black-and-white cat-foot") is a mammal classified in the bear family, Ursidae, native to central and southern China. The panda's main food is bamboo, but they may eat other foods such as honey, eggs, fish, and yams. Easily recognizable through its large, distinctive black patches around the eyes, ears and on its rotund body, the giant panda is an endangered animal: an estimated 1,600 pandas live in the wild and some 188 were reported to live in captivity at the end of 2005, twenty of which are found outside of China. However, reports show that the panda numbers in the wild are on the rise. The giant panda has a very distinctive black-and-white coat, .大熊猫大熊猫（大熊猫"非黑即白猫脚"）是在熊科，Ursidae分类哺乳动物，原产于中国中部和南部。
教室里的不明飞行物英语作文
教室里的不明飞行物英语作文In the hallowed halls of Willow Creek High, where knowledge seekers converged, an enigmatic occurrence unfolded, leaving students and faculty alike perplexed and intrigued. Amidst the mundane humdrum of algebra equations and literary interpretations, an unidentified aerial object, defying all known laws of physics, made its uncannypresence known.It was during the second period, as Mrs. Hawthorne droned on about the intricacies of the Pythagorean theorem, that the classroom's tranquility was shattered. A faint hum, akin to the buzzing of a thousand bees, reverberatedthrough the air, growing in intensity with each passing moment. Suddenly, a shimmering, iridescent sphere emerged from the corner of the room, hovering effortlessly in midair.The classroom erupted in a cacophony of gasps and whispers. Students abandoned their textbooks and scrambledto their feet, their eyes riveted on the celestial interloper. Mrs. Hawthorne, her lesson forgotten, stood frozen at the chalkboard, her chalk poised mid-sentence.The sphere, measuring approximately the size of a basketball, possessed an ethereal glow that seemed to defy description. Its surface shimmered with an iridescent array of colors, shifting from emerald green to azure blue to crimson red. No discernible features could be discerned, save for an intricate pattern of swirling lines that adorned its surface.As the minutes ticked by, the sphere remained suspended in the air, taunting the observers with its enigmatic presence. Some students, their curiosity outweighing their fear, cautiously approached the object, their hands trembling. To their astonishment, they discovered that it was intangible, their fingers passing through it as if it were made of thin air.Rumors about the classroom's UFO spread through the school like wildfire. Students from neighboring classesflocked to the scene, eager to witness the phenomenon firsthand. The principal, Mr. Jenkins, a burly man with a skeptical demeanor, arrived on the scene and ordered the room to be evacuated.Undeterred, a handful of students lingered outside the classroom, their eyes fixed on the window. Through the glass, they could see the sphere hovering motionless, its ethereal glow casting an otherworldly aura upon the room.As the school day drew to a close, the UFO abruptly vanished, leaving no trace of its existence. The room was returned to its previous state, save for the lingering whispers and the unanswerable questions that haunted the minds of those who had witnessed the extraordinary event.In the aftermath of the incident, theories abounded asto the nature of the UFO. Some dismissed it as a mere prank, a clever hoax perpetrated by mischievous students. Others speculated that it was a sign of extraterrestrialvisitation, a harbinger of an impending invasion. Still others suggested that it was a manifestation of a paralleldimension, a doorway to another realm.Despite the countless theories and speculations, the true nature of the Willow Creek UFO remains unknown. The event has become a local legend, a tale recounted in hushed whispers and passed down through generations of students. And so, in the hallowed halls of Willow Creek High, the enigma of the UFO lingers, a reminder of the vastness of the unknown and the enduring fascination with thepossibility of life beyond our own.。
[英语作文]磕头虫
![[英语作文]磕头虫](https://img.taocdn.com/s3/m/c83424af534de518964bcf84b9d528ea80c72f6a.png)
[英语作文]磕头虫Title: The Resilience of the Ladybug: A Tale of Tenacity and CharmIn the vast and diverse world of the insect kingdom, there exists a creature that has captured human attention and affection for centuries - the ladybug, often playfully referred to as the "lady beetle" or, in some cultures, the "lucky bug." Despite its diminutive size, this tiny creature embodies resilience, tenacity, and the power of symbolism. Its story is one of adaptability in the face of adversity, and its presence is often seen as a harbinger of good fortune.The ladybug's scientific name, Coccinellidae, hints at its vibrant red coloration, which varies from species to species but is most commonly associated with the classic bright red with black spots. This coloration not only adds to the ladybug's charm but also serves as a form of natural defense against predators. The spots warn potential threats that these insects secrete a distasteful substance when attacked, making them an unappealing meal.Ladybugs are not just aesthetically pleasing; they are also valuable contributors to the ecosystem. They are voracious predators of plant-sucking insects like aphids, scale insects, and various soft-bodied pests. By keeping these populations in check, ladybugs help protect crops and ornamental plants, making them a favored companion in many gardens and farms. Their presence is often celebrated, as they are seen as natural allies in the battle against pests.However, the road for the ladybug is not always smooth. Like many insects, they face environmental challenges such as habitat loss, climate change, and the use of pesticides. Yet, they demonstrate remarkable adaptability, finding new habitats and food sources when their traditional ones are compromised. Their ability to fly allows them to disperse widely, seeking refuge and opportunity in new locations.The ladybug's role as a cultural symbol adds another layer to its story. In many cultures, it is considered a bringer of good luck and prosperity. Its appearance is often associated with positive omens, and its gentle nature has endeared it to people across generations. Children are often told that if a ladybug lands on them, it is a sign of good fortune, and killing one would bring bad luck.The ladybug's influence extends to art and popular culture as well. It has been immortalized in literature, children's books, and even on the big screen. Its distinctive shape and coloring have made it a favorite subject for artists and designers, adorning everything from home décor to fashion accessories.In conclusion, the ladybug's tale is one of perseverance and charm. Despite being small in stature, it has carved out a significant place in our hearts and ecosystems. Its ability to thrive in the face of challenges serves as an inspiration for us all. As we observe these winged wonders flitting from plant to plant, we are reminded of the beauty and importance of biodiversity and the need to protect it. The ladybug's legacy is a testament to the strength and value found in even thesmallest creatures that share our world.。
去菜市场买菜带虫洞的作文
去菜市场买菜带虫洞的作文Going to the market to buy vegetables with wormholes is a common problem that many people face when purchasing fruits and vegetables.去菜市场买带虫洞的蔬菜是很多人在购买水果和蔬菜时面临的普遍问题。
It is frustrating to see all the efforts put into selecting the freshest produce go to waste when discovering wormholes in the vegetables.当发现蔬菜上有虫洞时，所有精心挑选最新鲜农产品的努力都会化为泡影，令人心情沮丧。
Not only is it disappointing to find wormholes, but it also raises concerns about the quality and safety of the vegetables.发现虫洞不仅令人失望，还引发了对蔬菜质量和安全性的担忧。
Consumers are left wondering if the vegetables with wormholes are safe to consume, leading to a loss of trust in the food supply chain.消费者担心带虫洞的蔬菜是否安全食用，这导致他们对食品供应链的信任丧失。
While some may argue that wormholes are a natural part of the growth process for fruits and vegetables, others believe that it is a sign of poor quality control and hygiene standards.一些人可能会认为虫洞是水果和蔬菜生长过程中自然的一部分，而其他人则认为这是质量控制和卫生标准不高的表现。
介绍蝴蝶的生长过程英语作文小学
介绍蝴蝶的生长过程英语作文小学全文共6篇示例，供读者参考篇1The Amazing Life of a ButterflyHi everyone! Today I'm going to tell you all about how a butterfly is born and grows up. It's such a cool process! Butterflies go through an amazing transformation called metamorphosis. This big word means they change their entire body and look completely different at different stages of life. Isn't that wild?It all starts when a butterfly lays her eggs on a special kind of plant called a host plant. The mommy butterfly can only lay her eggs on certain plants that her caterpillar babies will be able to eat when they hatch. She has to choose very carefully! Some butterflies like to lay their eggs on leaves, while others tuck them into cracks in tree bark or even underground. The eggs are so tiny, but if you look closely they are beautiful colors like green, yellow, red or white.After a little while, the eggs start to wiggle and shake. A tiny caterpillar pokes a hole and emerges! This is the second stage ofthe butterfly life cycle - the larva stage. We call them caterpillars now. The newborn caterpillar's first job is to eat the rest of its own egg casing for a bit of food to get going. Then the hungry caterpillar starts munching on the host plant leaves around it. That's all it will do for the next couple of weeks - eat and eat and eat! The caterpillar grows so big that it can't fit in its skin anymore. So what does it do? It molts!Molting is when the caterpillar sheds its skin to allow its bigger body to keep growing. It's pretty gross looking - the caterpillar attaches itself to a twig or leaf by some special grips on its body called prolegs. Then it wiggles out of its old skin! If you've ever seen a snake skin lying around after a snake shed it, it's kind of like that. The old skin is left behind in one piece and the caterpillar has a bright new stretchy skin underneath. Cool, right?Most caterpillars go through 4 or 5 molts, shedding their skin each time. As they grow, many caterpillars change color and pattern too. Some have special camouflage looks to hide from predators like birds. After its final molt, the supersized caterpillar is now ready for the next big change – the pupa stage!The caterpillar stops eating and finds a cozy spot, either on a plant or somewhere protected off the ground. It attaches itselfwith a bit of silk and begins to wiggle and squirm crazily. Eventually its outer skin splits and falls off to reveal an amazing pupa underneath! The pupa is like a little nudged capsule with no mouth or legs. It's the strangest thing – inside this little shiny case, the caterpillar's body is basically melting into a sort of insect soup! Then incredible cells in this "soupy" material reorganize themselves into an entirely new creature - a butterfly!The pupa is like a safe little home where all the magic happens over 1-2 weeks. You can sometimes see the butterfly forming inside if the pupa is clear or has cool patterns and colors. When I've watched one hatch before, it looks like the pupa twitches a little bit from the butterfly moving around inside. Then a slit opens and you see a crumpled up butterfly slowly emerge!The new butterfly has to spend some time drying its wings and plumping them up before it can fly away. Its wings start out small and shriveled but fill with fluid and nutrients. They expand into those big, beautiful butterfly wings we all recognize. Once the wings are nice and dry, the butterfly takes its first flight! It's so amazing to think that just a little while earlier, it was a humble little caterpillar chomping on leaves.The butterfly only lives a couple weeks, but in that time it will drink nectar from flowers using its long straw-like mouth called aproboscis. It will find a mate and then the female lays new eggs to begin the cycle all over again. What an unbelievable process! From a tiny speck of an egg, to a hungry caterpillar, to a weird pupa case, and finally emerging as a stunning butterfly.Nature is so cool, isn't it? I hope you learned something new about how these amazing insects transform. Next time you see a butterfly, I hope you take a moment to appreciate the long journey it went through to get those beautiful wings. Thanks for reading my essay!篇2The Amazing Life of a ButterflyHi everyone! Today I'm going to tell you all about how a butterfly is born and grows up. It's one of the most incredible things in nature. Butterflies don't start out as the beautiful creatures we all know and love. No way! They go through an amazing transformation called metamorphosis. It'smind-blowing!It all starts when a female butterfly lays her eggs. She has to be super careful about where she puts them. The eggs need to be on a plant that the butterfly babies (called caterpillars) can eat when they hatch. Different kinds of butterflies like differentplants. Some love milkweed, others want cabbage or fennel. The mom has to find just the right plant to give her young'uns the best start.After a few weeks of just chilling as an egg, a tiny caterpillar will emerge! This is called hatching. The caterpillar is really hungry right away because it needs a lot of energy to grow. It spends pretty much all day and night munching on the plant leaves around it. Caterpillars are eating machines!As the caterpillar eats more and more, its outer skin gets too tight and can't stretch anymore. That's when it sheds the old skin in a process called molting. The caterpillar grows a nice new skin that has room for it to keep expanding. Cool, right? Most caterpillars have to molt several times while they are growing up.Once the caterpillar gets huge and can't grow any bigger, it's time for the next stage. This is where the magic truly happens! The caterpillar finds a cozy spot and transforms into a pupa (say "POO-puh"). Depending on the type of butterfly, the pupa might be attached to a branch hanging upside down, or it could be hidden in leaves on the ground. This pupa stage is like being in a sleeping bag. The caterpillar is technically still alive in there, but it's almost like hitting a pause button.Inside this little cocoon or chrysalis (say "KRISS-uh-liss"), some unbelievable changes start happening. It's like the caterpillar is melting and completely rearranging itself into an entirely new creature! It develops a long tube for a body, skinny legs, intricate wings, and beautiful patterns and colors. From the outside, the pupa case doesn't look like much is going on. But on the inside, it's pure magic!Finally, after a few weeks or even months of this transformation, the pupa cracks open. Out emerges one of the most awesome insects on the planet - a butterfly! At first, the butterfly's wings are tiny and crumpled. But it pumps body fluid into them to make them unfurl and get bigger. Then the butterfly has to rest while its wings dry out fully before it can take flight.Once those wings are ready, the butterfly's new life begins! It might only live for a couple of weeks, but it's got a crucial job to do. The butterfly has to find a mate and start the cycle all over by laying eggs for the next generation. Butterflies are also really important for pollination, which helps plants grow and produce food we can eat.I think it's just astonishing how a butterfly begins as a tiny egg and becomes a chubby little munching machine. Then ittakes a long nap in a pupa cocoon while literally rearranging its entire body into a graceful flying insect! It makes you wonder what other awesomely bizarre stuff happens in nature that we don't even know about.I really hope you found this as fascinating as I do. Butterflies are living proof that amazing changes can happen when you give it time and have a little patience. Like the caterpillar turning into a butterfly, maybe we can transform ourselves into who we're truly meant to be too! Thanks for reading, friends!篇3The Magical Life of a ButterflyHi friends! Today I want to tell you all about one of the most amazing tiny creatures on our planet - the butterfly! Butterflies are beautiful insects with big colorful wings that flit and flutter through the air. But did you know that butterflies didn't always look like that? They actually go through an incredible transformation called metamorphosis to become those graceful flying flowers.A butterfly's life starts out as a very small egg, tinier than a speck of dust! The mother butterfly lays her eggs on the leaves of a plant that she knows her babies (called caterpillars) will beable to eat when they hatch. After a little while, a tiny caterpillar no bigger than a rice grain emerges from the egg.This is just the first stage of a butterfly's life cycle! The caterpillar's only job is to eat and eat and eat some more to grow big and strong. It munches on the leaves of the plant, getting bigger with each bite. As it grows, the caterpillar has to shed its skin several times, almost like how we outgrow our clothes and need new ones. Isn't that wild?The caterpillar keeps on munching for 2-4 weeks until one day, it stops eating and starts looking for a nice safe place to rest. This is when the real magic happens! The caterpillar attaches itself to a twig or leaf and begins shedding its skin one last time. But this time, something different emerges - a hard protective shell called a chrysalis.Inside this little capsule, the caterpillar's body is rapidly transforming through an amazing process called metamorphosis. Its body breaks down into a sort of insect soup, and then incredible new parts start to form - legs, antennae, a proboscis (a long tongue for sipping nectar), and those grand vibrant wings we all admire! After a few weeks to a month inside the chrysalis, a brand new creature is ready to make its entrance into the world.The chrysalis cracks open and out emerges a beautiful, delicate butterfly! Its wings are soft and crumpled at first, but it pumps fluids from its body into the wings to make them grow full and flat. Once its wings are dried and ready, this magnificent insect takes its very first fluttery flight!Can you imagine going through such an unbelievable change? From a tiny egg to a hungry little caterpillar to ajade-green chrysalis and finally blossoming into a graceful winged artist of the skies? It's like magic!The butterfly only has a few weeks to live its final life stage. It flits from flower to flower, drinking sweet nectar with its long tongue and helping to pollinate plants in the process. Some travel thousands of miles on their delicate wings to warmer regions when winter comes. The female butterflies even find a cozy plant to lay their eggs on before their short but amazing lives come to an end.And so the incredible cycle begins anew, with those tiny eggs waiting to hatch into caterpillars and one day emerge as beautiful new butterflies themselves. Nature is full of these astonishing miracles happening all around us if we just take a moment to look!I hope you've enjoyed learning about the magnificent life journey of the butterfly. The next time you see one delicately dancing on the wind, remember the epic adventure it went through to become that vibrant painting in the sky! Nature is truly full of magic and wonder.篇4The Amazing Life of ButterfliesHi there! My name is Jamie and today I want to tell you all about the incredible life cycle of butterflies. Butterflies are one of the most beautiful and amazing creatures on our planet. Did you know that butterflies don't start out as butterflies? They go through an amazing transformation called metamorphosis before becoming those colorful, winged insects we all know and love.It all starts when a butterfly lays her eggs. The butterfly mama carefully picks the perfect spot to lay her eggs, usually on a leaf of the plant that the baby caterpillars will eat when they hatch. Some butterflies lay their eggs one by one, while others lay them in clusters. After a few days or weeks, tiny caterpillars emerge from the eggs!These baby caterpillars are called larvae. They don't look much like butterflies at all at this stage. Caterpillars are little wriggly creatures with lots of stubby legs. Their main job is to eat...and eat...and eat some more! You see, caterpillars need to consume a huge amount of food to gain enough energy for the next stage of their lifecycle. Some caterpillars can eat an entire plant before they are done growing!As the caterpillar eats, it grows bigger and bigger. Eventually it sheds its skin, which is called molting. Caterpillars actually molt several times as they continue to devour leaves and grow larger. After their final molt, the caterpillar is full-grown and it's time for the next amazing step - forming a chrysalis!The caterpillar attaches itself to a twig or leaf using a bit of silk, and hangs upside down in a funny curved shape called a 'J'. Then its skin splits one last time and it wiggles out of its outer caterpillar skin altogether! What's left is an amazing protective case called a chrysalis or pupa. The chrysalis is usually a cool green color that helps camouflage it on the plants.Inside this little chrysalis case, the most mind-blowing transformation takes place. The caterpillar's body completely dissolves into a kind of insect soup! This gooey substance then reforms itself cell by cell into an entirely new creature - abutterfly! The butterfly grows all new legs, a proboscis for drinking nectar, eyes, wings, and all its other body parts from this butterfly soup inside the chrysalis. Isn't that wild?After a period of about 1-2 weeks inside the chrysalis, a beautiful butterfly emerges! It has to pump fluid from its body into its wings to unfurl them and let them dry out. Once its wings are ready, the butterfly takes its first flight. Adult butterflies only live for a couple weeks, just long enough to mate and for the female to lay more eggs to begin the cycle all over again.There are so many amazing types of butterflies all around the world, from the huge blue Morpho butterflies of the rainforests to the iconic orange and black Monarch butterflies that migrate thousands of miles each year. No matter the species, all butterflies start out as tiny eggs, become hungry little caterpillars, pupate in a chrysalis, and then emerge as those entrancing flying flowers we call butterflies.I hope you found the life cycle of butterflies as fascinating as I do. Next time you see a butterfly, remember the long journey it went through to get those beautiful wings. The butterfly life cycle is one of the most magical transformations in nature. Isn't it amazing what these delicate creatures can do? That's the truly wonderous story of how a butterfly is born!篇5The Wonderful Life of ButterfliesHey kids! Have you ever watched a butterfly fluttering around in the garden and wondered how it became such a beautiful creature? Well, buckle up because I'm going to tell you all about the amazing life cycle of butterflies!It all starts with a tiny egg, smaller than a speck of dust. A butterfly mommy, called a female, lays her eggs on the leaves of plants. She's very picky about where she puts them because when the babies hatch, they'll need that plant for food. Butterfly babies are called caterpillars and different types of caterpillars like to munch on different plants.After a few days or weeks of waiting, a teeny tiny caterpillar emerges from the egg. At this stage, the caterpillar is called a larva. It's just a pudgy little baby but boy, can it eat! It spends almost all its time chowing down on leaves to help it grow big and strong.As the caterpillar keeps eating and eating, its skin keeps getting tighter and tighter. But no worries, it can shed that old skin like you shed your outgrown clothes! This shedding is called molting. After each molt, the caterpillar has a brand new skin togrow into. Caterpillars molt several times before they reach their full size.Once a caterpillar can't grow any bigger, it's time for the next stage called the pupa or chrysalis. The caterpillar attaches itself to a twig or leaf using sticky silk threads it makes from special glands in its mouth. It then sheds its outer skin one last time, revealing an amazing transformation underneath!Inside the pupa, which looks like a tiny egg or jaw-dropping jewel depending on the type of butterfly, the caterpillar is rapidly changing. It's turning into a butterfly through an incredible process called metamorphosis. Incredible cells and tissues are forming like wings, a proboscis for sipping nectar, and beautiful color patterns on its new body!After a few weeks to months of this magical transformation, the pupa case cracks open and out emerges one of the most magnificent creatures on Earth - a butterfly! Its wings are soft and crinkly at first, but it pumps body fluid through them to make them big, flat, and stretched out.Once its wings are dry, the butterfly takes its first flight into the world. It flutters and floats from flower to flower, drinking sweet nectar with its long straw-like proboscis. The female willmate with a male butterfly and start the whole life cycle over again by laying more eggs on plants.Isn't the life of a butterfly just astounding? From a tiny egg to a munching caterpillar to a mind-blowing chrysalis to a graceful flying beauty, butterflies have one of the most amazing life cycles in nature! Next time you see a butterfly, remember the long journey it went through to get there. They are living rainbows showing us the magic of metamorphosis.I hope you loved learning about the butterfly life cycle as much as I enjoyed telling you about it. Keep exploring and discovering the wonders of our incredible planet! Who knows what amazingcreature you'll learn about next?篇6The Amazing Life of a ButterflyHi everyone! Today I want to tell you all about the incredible life of a butterfly. Butterflies are one of the most wonderful creatures in nature, and their life story is simply amazing. From a tiny egg to a beautiful winged insect, the journey of a butterfly is full of surprises and amazing changes. Let me walk you through it!It all starts with an egg. The butterfly lays her eggs on the leaves of plants that her caterpillar babies will eat after they hatch. The eggs are really tiny, but if you look closely you can see them attached to the leaves. They almost look like little jewels sparkling in the sun.After a little while, the egg starts to change. It gets a little crack and then...out comes the caterpillar! This little guy is called a larva. He doesn't look much like a butterfly at all. The caterpillar is like a funny little worm with lots of legs. His main job right now is to eat as much as he can to help him grow big and strong.The caterpillar starts munching away on the plant leaves, eating and eating all day long. As he eats, he grows and grows, getting bigger and bigger. But there's something really weird that happens every so often. The caterpillar's outer skin gets too tight and crusty, and he can't move very well in it. So what does he do? He sheds his skin! That's right, he crawls right out of his old skin like taking off a jacket that's too small. Under that old skin is a brand new, bigger skin to give him room to keep growing. Caterpillars shed their skins several times as they get bigger and bigger.Once the caterpillar has grown as big as he can get, it's time for another huge change. The caterpillar makes a little hangingnest for himself called a chrysalis. Inside the chrysalis, the most amazing transformation happens - the caterpillar actually digests itself and reforms into a butterfly! Can you believe that? It's like the caterpillar turns into a butterfly soup and then rebuilds itself into a beautiful winged insect. Wild, right?The chrysalis protects the butterfly while this incredible change is happening inside. After a few weeks or months of waiting, a crack appears in the chrysalis. The butterfly inside pushes and wiggles until finally it emerges, wet and crinkled up. It hangs upside down for a while, pumping fluid into its wings to make them unfurl into their full majestic shape. Once its wings are nice and dry, the butterfly takes off into the sky!As an adult butterfly, its main goals are to find food like nectar from flowers and to find a mate. Butterflies don't live very long as adults, usually just a few weeks. But in that time the female butterflies lay lots and lots of eggs to start the life cycle all over again. Isn't that amazing?From a tiny speck of an egg to a funny little caterpillar gobbling leaves, and then turning into a beautiful flying butterfly - what an unbelievable journey! The next time you see a butterfly fluttering around in your yard or garden, remember the fantasticchanges it went through to get there. Butterflies are one of nature's coolest wonders!。
高中英语北师大版必修第二册Unit5HumansandNatureReadingClub课后练习、课
一、根据汉语意思填写单词(单词拼写)1. The secret of success is ________(诚实) and fair dealing. (根据汉语提示单词拼写)2. Permit me to offer you my ________(真诚的) congratulations. (根据汉语提示单词拼写)3. We set out on this voyage of ________(探索) with an open mind. (根据汉语提示单词拼写)二、完成句子4. The colours of the flowers ________(从黄到红不等). (根据汉语提示完成句子)5. 很遗憾你昨晚没有参加聚会。
___________you didn’t attend the party last night.三、根据所给汉语提示填空6. There are few people nowadays,________ (如果有的话), who remember him. (根据汉语提示完成句子)7. This collection ________________ (由……构成) three parts: poems, essays and short stories. (根据汉语提示完成句子)8. She________(吓得要死) at the strange noise. (根据汉语提示完成句子)四、汉译英（整句）(翻译)9. 你最好尽快为志愿工作做好准备。
(汉译英)五、阅读选择(阅读理解)文章大意：本文是一篇说明文。
主要介绍的是一种会飞行的作物帮手——瓢虫。
10. What do you usually do when a flying insect lands on your arm? Most likely you blow it away. But what if that bug is a ladybug(瓢虫)? Then chances are that you would let it stay. What is it about ladybugs that we like?Farmers once thought ladybugs were a good luck sign. A ladybug in the field meant that the crops(庄稼) would be successful and the weather would be good. The farmers may have been exaggerating(夸大) about what a very small bug can do, but in fact ladybugs do help out with the crops. They eat harmful insects.Actually, it is not the ad ult ladybug that eats the other insects. It’s the ladybug larvae(幼虫). Ladybugs lay their eggs on leaves that are covered with aphids or other insects. When the larvae come out of the eggs, they are very hungry and will eat mites, aphids, mealybugs, green flies, and other crop-destroyers.A single ladybug larva can eat over 1,000 aphids in one day. In the 1800s, ladybugs were brought all the way from Australia to California and set free among orange trees that were dying from being eaten by insects. The litt le red and black “eating machines” completely saved all the trees.Ladybugs go about their daily business without worrying much about anything. Very few birds or insects will eat a ladybug because it gives off something that is dangerous to eat. Ladybugs also protect themselves by playing dead. They fall off leaves and remain very still until their enemy goes away.So next time you see a ladybug, think about what it may be up to. Maybe it is off to save an orange tree. Maybe its next move will be to fall off a leaf and play dead or stand up to a bird about 100 times its size. Maybe it’s letting you know that the weather will be good tomorrow. Who knows? Ladybugs are special.1. What do we know about mites and aphids?A．They do harm to the crops. B．They eat more than they should. C．They are food for adult ladybugs. D．They are the enemy of ladybug larvae. 2. What does the underlined part “stand up to” in the last paragraph probably mean? A．Play with. B．Worry about. C．Get along with. D．Fight back against.3. What does the author think of the ladybug?A．It is a crop-destroyer. B．It is a good luck sign.C．It is a little flying helper. D．It is a big eating machine.文章大意：本文是一篇说明文。
《竹节虫》初三英语作文
《竹节虫》初三英语作文Stick insects, also known as "Kongming locks", are one of the longest insects in the world, with a maximum body length of 33 cm. Most stick insects are green or yellow-brown, which is very similar to the color of bamboo branches, allowing them to blend perfectly into the surrounding environment and go unnoticed. Their appearance is similar to bamboo branches, and it is difficult to tell whether they are real or fake when they crawl on bamboo branches, which is amazing. Stick insects usually come out at night and feed on the leaves of plants. They move slowly and often lie still on branches during the day, making them difficult to be discovered.However, stick insects are not just ordinary insects, they also have excellent camouflage ability. When frightened, stick insects will immediately enter a state of suspended animation, as if dead, to avoid being discovered by natural enemies. In addition, some stick insects can also spray milky white liquid for self-defense, which is toxic and can cause harm to natural enemies.The order Phasmida, also known as the order in the past, is a group of medium or large insects known for their mimicry. There are many species of stick insects with different shapes. Some resemble bamboo joints or branches and are called stick insects or; some resemble leaves and are called leaf insects or leaves. The body color of stick insects is mainly green or brown, which blends in with the surrounding environment and plays a good protective role. At present, there are about 2,000 known species of stick insects, which are widely distributed in tropical areas.Although stick insects may not look impressive in appearance, their names are very beautiful. Some of them, such as "qinsi stick insect" and "zhonghua yexiu", are full of poetic and cultural connotations. These names not only reflect people's love for stick insects, but also reflect their unique status in nature.In Australia, scientists have announced an exciting news: prehistoric stick insects that were thought to have been devoured by wild mice more than 80 years ago still have a few living on islands off the coast of Australia. However, surprisingly, the stick insects that have been found since the Jurassic period are all female, forming a unique matriarchal society. This discovery has excited scientists and has given people a deeper understanding of the evolution of stick insects.Stick insects evolved even earlier than dinosaurs, making them an important target for studying biological evolution. Recently, scientists came to the Pyramid of Balls, a volcanic rock protruding 23 kilometers from St. Hewes Island, to investigate the rumored discovery of a large-headed stick insect. This insect is unique and one of the rarest species in the world. Its closest relative may be a stick insect living in the jungles of New Guinea.Through the study of stick insects, we can not only understand their ecological habits and camouflage skills, but also draw important inspiration about environmental protection and biodiversity. The living environment of stick insects is threatened by human activities, such as deforestation and over-cultivation. Therefore, protecting stick insects and their living environment is of great significance to maintaining ecological balance and biodiversity.In short, stick insects, with their unique charm and wonderful ecological habits, have become an indispensable part of nature. We should respect and protect these precious biological resources, let them continue to thrive on the earth, and add more color and vitality to our world.。
有关寄生生物的英语作文
有关寄生生物的英语作文Parasites are everywhere. They can be found in animals, plants, and even humans. These tiny creatures live off of their hosts, often causing harm or discomfort. Some parasites, like tapeworms and fleas, are well-known for their ability to cause diseases and infections.Parasites come in all shapes and sizes. From microscopic protozoa to larger worms, they have evolved to thrive in a wide range of environments. Some parasites are able to manipulate their hosts in order to ensure their own survival, while others simply feed off of their host's nutrients.One of the most fascinating things about parasites is their ability to adapt and evolve. They can develop resistance to medications and find new ways to infect their hosts. This constant battle between parasites and their hosts has led to some of the most deadly diseases in history, such as malaria and sleeping sickness.Despite their negative reputation, parasites play an important role in the ecosystem. They help control the population of their hosts and can even influence the behavior of entire species. In some cases, parasites have been used to control invasive species and protect native ecosystems.Parasites are a constant reminder of the complex and interconnected nature of life on Earth. They challenge our understanding of biology and force us to reconsider our place in the natural world. As we continue to study and learn about parasites, we may discover new ways to protect ourselves and the environment from their harmful effects.。
虫洞
• In conclusion, we the black hole, hole and the wormhole essence know little, they still mysterious things, many problems still need to further explore. Now astronomers have indirectly find black hole, but the hole, the wormhole has not found, was a frequently appear in works of science fiction in theory noun.
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The wormhole properties
• the use of relativity without considering some quantum effect and besides the attraction outside of any energy, we get some very simple, basic on the wormhole description. The description is very important, because the focus of our study is a black hole, and the
• universe is not in the hole, so I am here simply introduce the wormhole nature, and for some related theory and the theory of description, this does not involve.
公园里开满了各种颜色的花用英语作文
公园里开满了各种颜色的花用英语作文全文共5篇示例，供读者参考篇1The Park Full of Rainbow FlowersWow, you'll never believe what I saw yesterday! Mom and Dad took me to this amazing park and it was like walking into a rainbow explosion. Flowers were blooming everywhere in so many bright, beautiful colors. It was like a dream!We walked down the path and the first flowers I noticed were the red ones. They were these big, puffy roses that looked like fluffy clouds. I wanted to reach out and touch their soft petals, but Mom said I shouldn't pick the flowers so others could enjoy them too. The roses had a sweet, pretty smell that made me think of candy.Next to the roses were sunflowers! These were the tallest flowers, stretching up higher than me. Their yellow petals circled big brown centers that looked like smiley faces. I felt like the sunflowers were looking down at me and smiling. They seemed so cheerful and friendly. I bet sunflowers are the happiest flowers.As we kept walking, I saw splashes of purple dotting the grass. Moving closer, I realized they were bunches of lilacs! The tiny purple blossoms were clustered together in cone shapes. I cupped my hands under one and was surprised by the heavenly floral scent. It reminded me of Mom's nice perfume. The lilacs were so small but packed a powerful punch of sweetness.Then the most eye-catching flowers of all came into view - the tulips! There were tulips everywhere in every color you can imagine. Red, pink, yellow, purple, and even tulips with stripes and petals of multiple colors on the same flower. The tulips made me think of a rainbow arched across the lush green grass. They looked like nature's celebration with their cheery, cupped blooms facing the sun. Of all the flowers, the tulips were definitely my favorite.Have you ever seen a flower that's not just one color, but has streaks and designs of different shades? That's what caught my eye next - the iris flowers. Some irises were purple with yellow streaks, while others were bright orange with deep blue designs. They were like little works of art! Up close, the petals looked like soft velvet tapestries with elegant patterns. Irises must be the fanciest flowers.It wasn't just the bigger, showier flowers that decorated the park though. I noticed some delicate white blossoms scattered along the edges of the path. Dad told me they were called baby's breath. Isn't that the cutest name? The tiny flower clusters looked just like little clouds or puffs of smoke. They added a soft, hazy beauty to the more vibrant flowers around them.With so many colors everywhere I looked, it felt like I was in a kaleidoscope! The blues, pinks, yellows, oranges, purples, reds - they all blended into one big rainbow. The Park was absolutely overflowing with every color of flower you can dream of.As we walked along, butterflies and bumblebees flitted from bloom to bloom. It was like the flowers were having their own party with these colorful insect guests. The butterflies were like flying pieces of confetti and the bees hummed merrily as they danced from flower to flower. I tried standing really still so maybe a butterfly would land on my nose, but they must have been too interested in the yummy flowers.The best part was the heavenly scent that hung in the air everywhere we went. It was like someone combined all the most delicious perfumes and baked a birthday cake - then sprinkled it with sugar and spice and everything nice. One second, I could smell the bold rosiness. The next, I caught a whiff of the crisp,herbal greenery mixed with lilac's sweet breath. The smells made me feel happy and sunny inside, like I was in my own magical world.After slowly wandering and admiring every inch of the floral wonderland, I was feeling a little sleepy from all the sights and scents. We found a patch of grass under a shady tree to sit down and have our picnic lunch that Mom packed. As I nibbled on my sandwich, I gazed out at the Rivers of color surrounding me. It was like the most beautiful painting had bloomed to life right before my eyes. Only this painting smelled as pretty as it looked!That night when I went to bed, I wished I could dream in color so I could see the Park's flowers again. I never wanted to leave that happy, rainbowed place. If the world were filled with that many colorful blooms everywhere you looked, I think everyone would walk around with a smile permanently planted on their face. Flowers just have a way of blanketing the world in warmth, happiness and pure beauty.I'm already asking Mom and Dad when we can go back to the Park again. There's no doubt I'll be spending as many sunny days as I can living inside that floral kaleidoscope this spring and summer. Maybe next time, a rainbow-colored butterfly will landon me! A kid can dream, right? As long as that dream is full of flowers.篇2The Park Full of Colorful FlowersWow, you won't believe the park I went to yesterday! It was the most amazing, colorful place I've ever seen. My mom took me and my little sister there for a picnic. When we first got there, I thought it looked like a regular park. There were some trees, a playground, and lots of green grass. But then we walked a little further and that's when I saw it - the incredible flower gardens!It was like stepping into a rainbow paradise. Flowers were blooming everywhere in every color you can imagine. Reds, oranges, yellows, greens, blues, purples, pinks - so many colors all mixed together. The gardens seemed to go on forever with winding paths leading you around each new section. I couldn't wait to explore them all!We started down one of the paths and the first flowers we saw up close were these humongous red ones. They were as big as basketballs! The petals were so velvety and soft. I wanted to snuggle up and take a nap inside one of the giant blooms. Mysister liked sniffing them because they had a sweet, rosy fragrance.Next we came across a patch of bright yellow sunflowers. Their heads were all facing the sun, staring up at the sky with their big smiley faces. I felt like they were happily greeting me. Some of them were taller than me! Their petals were very rough and prickly when I touched them. I pretended the sunflower patch was a field of smiling sun worshippers all stretching to get closer to their god.Around the bend, there was an area filled with every shade of pink, purple, and white flowers. The petals were so delicate and papery thin. It looked like a fairy princess garden. My sister and I played a game where we were tiny fairies flying from bloom to bloom, sipping nectar from the sweet-smelling petals. We had to be careful not to rip the fragile flowers when we landed on them. Such a pretty, magical place!Then we discovered the crown jewel of the gardens - an incredible rainbow flower tunnel! It went on and on, an arched pathway completely covered on the sides and top by interwoven vines and branches bursting with every colored bloom imaginable. As we walked through, it felt like we were inside a kaleidoscope constantly shifting and changing. Red flowers, thenyellow, green, blue, purple, orange, back to red again. The vibrant tunnel seemed to go on forever.Halfway through there was a secret fairy circle, a perfectly round garden surrounded by stones with a miniature toadstool village inside. Bushes around the circle were decorated with dangling orbs made of pink and purple petals clustered together. My mom called them "flower ball bushes." My sister and I became flower fairies again, flying from toadstool to toadstool and petal orb to petal orb. The most magical place in the tunnel for sure.After leaving the tunnel, the gardens opened up into vast fields of wildflowers. A sprawling landscape covered in splashes of every color - sunny goldenrods, passionate red poppies, pure white daisies, vivid purple asters, brilliant orange tiger lilies. We ran through the fields, flower petals brushing our legs as we raced by. When we finally collapsed down in the flowers, I made a little nest to lay in, surrounded by the vibrant blooms and their sweet, earthy scent.On our way out, we stopped at the Japanese garden section filled with ponds, little bridges, and flowering trees. Pale pink cherry blossoms floated down around us like flurry snow. I tried catching the petals on my tongue. They tasted like honey! Anarched bridge over a koi pond was absolutely covered in vines of cascading blue and purple wisteria blossoms. I had to duck down to avoid getting bonked on the head as I walked under thelow-hanging blooms. So pretty!The flower gardens were definitely the most amazing thing I've ever seen. Just thinking about all the colors, smells, and beauty makes me smile hugely. I can't wait to go back and explore more of those incredible rainbow blooms! The flower fairies are waiting for me to return to their magical world.篇3The Park Full of Colorful FlowersWow, you'll never believe how pretty the park looked today!I went there with my mom and dad after lunch. We were just going to go on the swings for a little while, but then we saw the most amazing sight - the whole park was covered in flowers of every color you can imagine!When we first got there, I noticed some bright yellow flowers right near the entrance. They were sunflowers! My dad told me they were called that because their petals stick out like rays from the sun. They were so tall, I had to strain my neck to see theirsmiling faces turned towards the sky. I wish I was as tall as a sunflower!We kept walking along the path, and that's when I gasped - there were hundreds of red flowers dotted all over the grassy areas. "Tulips!" my mom exclaimed. The tulips looked like they were little cups made of silk, holding droplets of morning dew. I knelt down to get a closer look and their sweet perfume tickled my nose. I wanted to pick one to put behind my ear, but mom said we should leave them for everyone to enjoy.Further down the trail, I spotted a blaze of bright orange. "Look at those!" I shouted, tugging on my dad's sleeve. He laughed and said those were called marigolds. They reminded me of miniature suns shining up from the earth. I loved how the orange petals were tinged with yellow near the centers. As we got nearer, I could see the marigolds were surrounded by a sea of pure white flowers. Mom said those were daisies and that you could make daisy chains by carefully linking them together stem-to-stem. I hadn't brought any scissors to try that this time, but I made a mental note to come back soon and make the longest daisy chain ever!By this point, my eyes had gotten used to all the vibrancy and I started noticing some softer, more subtle colors too. Likethe pale purple irises, standing straight and tall like royal guards. And the sky blue hydrangeas clustered in thick bushes, almost seeming like they had tiny faces when you looked closely. Mom pointed out some lavender-colored stalks that she called foxgloves. They reminded me of the hollow bird whistles I've made out of blades of grass before, except these were plump and velvety.As we turned the corner, an explosion of pink hit my eyes. It looked like someone had shaken out all the confetti from every party in the world! The sweet smell was so strong, it almost made me dizzy. Dad told me those were all peonies, and they only bloomed for a few weeks each year so we were lucky to catch them at their peak. He scooped me up so I could see them better, and I just stared at the layers upon layers of ruffled petals, mesmerized. Some peonies were cotton candy pink, while others were deeper magenta or gorgeous corals. I never wanted to leave that spot!But there was still so much more to see! Nearby, there was a big patch of royal blue flowers with silky centers. Those were irises, mom explained. I bent down to touch one and its petals felt cool and papery. A little further on, I noticed some cheerfulblue and yellow clusters that reminded me of sparkly fireworks - those were bachelor's buttons according to dad.The path looped back towards the entrance, and that's when the biggest surprise of all came into view. In the very center of the park was a huge circle overflowing with rose bushes! Every rose color you can dream of was there - passionate reds, buttery yellows, cotton whites, sweet pinks, peaches, and even a few unusual shades I'd never seen before like this duskypurplish-gray. I caught myself holding my breath as we walked through the rose garden, not wanting to miss a single fragrant note.Mom pulled a little book out of her pocket and opened it to a map. She pointed to a key that showed all the different flower types and where they were located throughout the park. Then she winked at me. "Should we go around again and see if we can spot them all?" She didn't have to ask me twice!We spent the whole afternoon happily zigzagging across that park, playing I-Spy with the vibrant blooms. I learned so many new names - chrysanthemums, carnations, poppies, dahlias, zinnias - my head was spinning! But I didn't want the day to end. Everywhere I looked, there were more cheerful splashes of color to discover. Red and gold coreopsis, sunny yellowcosmos, fluffy purple asters - it was like walking through a kaleidoscope fairyland!When we finally had to head home for dinner, I was sad to leave the floral wonderland behind. But I made my parents promise to bring me back again soon. A garden that beautiful deserves multiple visits! I didn't realize parks could look so magical. I thought they were just for playgrounds and walking dogs. But now I know they can bloom into temporary dreamworlds too, full of nature's bright artworks.I already can't wait for my next trip back. Maybe I'll even bring a sketchbook along and practice drawing all the different flowers. Or press some petals to make colorful designs. There's just something about seeing so much vibrant life and beauty gathered together like that. It makes you feel happy down to your toes! Like the flowers are smiling just for you. I'm so grateful our park got to experience this burst of color, even if it doesn't last forever. Memories like this one will though - warm in my heart like the sunshine that helped all those blossoms unfurl.篇4The Park Full of Colorful FlowersWow, you guys will not believe how pretty the park looked today! I'm so excited to tell you all about it. My mom took me to the big park near our house after school. It's my favorite park because it has so many fun things there like swings, a sandbox, and even a little stream you can wade in when it's hot outside. But today the park looked extra, extra special.When we got there, the first thing I noticed was all the bright, beautiful flowers that seemed to be blooming everywhere I looked! There were flowers of every color you can imagine. It was like a rainbow had exploded all over the grass and gardens. Let me tell you about some of the amazing flowers I saw.First, there were tons of red flowers. They looked like they were on fire, burning so bright! I saw red roses, red tulips, and these other red flowers that looked kind of like fireworks. Mom said those ones are called dahlias. Next to the red flowers were bunches of sunny yellow flowers. They made me feel all warm and happy inside, just like when I go outside on a really nice day. There were yellows daffodils, yellow tulips, and these other yellow ones that looked like they had green tutus on. Mom called those green tutus "petals" but I like to think of them as little flower dresses!Then I saw some of the most vivid orange flowers. They were so orange they looked almost red! There were tiger lilies which are orange with black spots. I thought those were super cool looking. Mom pointed out the bright orange poppies too. We also found clusters of purple flowers that looked like little suns with rays sticking out. Those were crocuses according to Mom. I just thought they looked like excited flower people dancing and waving their arms!Of course, there had to be pink flowers too. We couldn't miss those big, ruffly pink peonies. They kind of reminded me of tutus that ballerinas wear. The pink azaleas looked like Pink clouds that had gotten stuck in the bushes somehow. Everything smelled so nice and sweet from all the different pink flower smells.My favorite flowers though were the blue ones. I never realized there were so many pretty blue flowers until I saw them all together at the park! There were light blue forget-me-nots that looked like someone had taken the sky and made it into a flower. The dark blue irises looked like they were staring back at me with their big Center's that mom called "stigmas." The other blue flowers I really liked were the bluebells. They hung downlike little bells and I could imagine cute flower people ringing them whenever the wind blew.As we walked around more, I noticed other flowers in fun colors too like white, coral, lavender, and magenta. It seemed like there were flowers blooming in every single shade. Mom told me that all the different types of flowers bloom at different times throughout spring and summer, but the park workers had planned it just right so we could see them all in bloom together for a little while. Isn't that so cool?I could have stayed at the park looking at the flowers all day. They were just so pretty and made me feel happy and cheerful inside. Before we left, I made mom promise we would come back again soon so I could see the flower rainbow another time. She said the flowers would look different as new ones bloomed and old ones faded, but that we could keep coming back again and again to watch it change throughout spring and summer. I can't wait!I'm so lucky we have such a nice big park so close to our house with so many fields and gardens full of flowers. Next time you come over, I'll take you to see it yourself! Just wait until you see all the vibrant reds, oranges, yellows, greens, blues, purples, pinks, and whites. Everywhere you look there are flowers, flowers,and more flowers in a zillion different shades. I wish the park could look that pretty and colorful all year round! Wouldn't that be the best? For now though, I'll just have to enjoy it while I can. Spring is finally here, hooray!篇5The Park Full of Colorful FlowersWow, the park looks so pretty today! There are flowers everywhere in a rainbow of beautiful colors. I'm going to tell you all about the different kinds I can see.First, let me tell you about the roses. Roses are my favorite flower because they are so classic and elegant. There's a big rose garden near the entrance with hundreds of rose bushes covered in velvety blooms. I see deep red roses that look almost black, with ruffled petals like fancy dresses. Nearby are sunny yellow roses that glow so brightly. And in between are pretty pink roses in all sorts of shades - pale baby pink, bold hot pink, and everything in between. The roses have a lovely perfumed scent that fills the air.Next to the rose garden is a field full of tulips! Tulips always remind me of spring because they bloom so early when everything else is just starting to wake up after winter. The tulipshere come in a kaleidoscope of hues. There are bright red ones that look like they are on fire. Purple and lavender tulips cluster together, their petals forming perfect cups. Lemon yellow tulips stand tall next to creamy white ones with brush strokes of pink on the edges. I even spot some unusual greenish tulips that resemble tiny pale tree frogs.As I wander further into the park, I discover several flower beds bursting with pansies. Pansies always look like little cute faces smiling up at me. They have such cheerful colors - sunshine yellow, violet purple, brilliant orange, and velvety blue-black. Some pansies even have funny mustache markings under their petals! The pansies swarm together in tidy little mounds, like a crowd of friendly people at a party.Hidden under some trees, I find patches of elegant lilies nodding in the breeze. There are regal white lilies, tall and pure like brides in their wedding dresses. I also see brilliant orange lilies speckled with maroon freckles, and pastel pink lilies blushing softly. The lilies have a heady sweet perfume that makes my nose tingle. I have to be careful not to get too close because the pollen could make me sneeze!Around the lily beds are clusters of puffy hydrangea bushes absolutely smothered in big round blooms. The hydrangeacolors are so unusual and beautiful - pale blue, deep purple, frosty green edged in red, and even a reddish-brown the color of rich hot chocolate. Each hydrangea bloom is loaded with dozens of tiny flower petals all huddled together to form one gigantic puffball. They look like they would be very fun to gently bop, but I won't touch because I don't want to hurt them.At the back of the park is a shady grove of trees where daffodils and crocuses are popping up from the leaf litter on the ground. Daffodils always remind me of the sun with their bright yellow trumpet shapes. But here I also find some white daffodils with orange centers, peaches and cream bi-colors, and even subtle lemon yellows tinged with pink. The crocus blooms carpet the ground in radiant purple, sunny yellow, and brilliant white stripes. It's like someone scattered a rainbow of jewels on the forest floor!Everywhere I look there are more types of flowers in every color imaginable. Frilly carnations clustered together like ballerinas in pink, red and white tutus. Stately irises standing up straight with ruffled purple petals. Chrysanthemums bursting into fuzzy pink, orange and yellow spheres. I'm completely surrounded by a riot of flowery hues that makes me feel so happy and alive!The park is vibrating with colors today and sweet fragrances waft through the air. Bees buzz from blossom to blossom, collecting golden pollen on their fuzzy legs. Butterflies flit above the flowers in kaleidoscopic flashes as brilliant as the blooms. I wish I could bottle up this beautiful scene and keep the colors and scents forever!After admiring all the incredible flowers, I find a perfect spot to sit and read my book surrounded by the splendid blossoms. I lean back against a cherry tree trunk covered in frothy pink blooms. Underneath me is a carpet of silvery purple phlox flowers that releases a delicious perfume when I brush against them. I gaze around at this riotous floral display and feel so grateful that flowers come in such an incredible rainbow of vivid colors and intricate designs. They are nature's artists, painting the landscape with dazzling brush strokes. The park looks like an Impressionist masterpiece come to life! I can't wait to come back again to admire this breathtaking flower show as the seasons change and new blooms take the spotlight. This special place is absolute flower paradise.。
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a r X i v :0709.3162v 1 [g r -q c ] 20 S e p 2007Some new class of Chaplygin WormholesF.Rahaman ∗,M.Kalam †and K A Rahman ∗AbstractSome new class of Chaplygin wormholes are investigated in the framework of a Chaplygin gas with equation of state p =−A:Observations of Type IA supernovae and Cosmic microwave backgroundanisotropy suggest that the Universe is currently undergoing an accelerated expansion [1-3].After the publication of these observational reports,theoretical physicists have been starting to explain this astonishing phenomena theoretically.It is readily understand that this current cosmological state of the Universe requires exotic matter that produces large negative pressure.It is known as dark energy and it fails to obey Null Energy Condition (NEC).To describe theoretically this ghost like matter source,Cosmologists have been proposed several propositions as Cosmological constant [4](the simplest and most popular candidate ),Quintessence [5](a slowly evolving dynamical quantity which has a spatially inhomogeneous component of energy with negative pressure ),Dissipative matter fluid [6],Chaplygin gas[7](with generalized as well as modified forms ),Phantom energy [8-10](here,the equation of state of the form as p =−wρwith w >1),Tracker field [11-12](a new form of quintessence )etc.Recently,scientific community shows great interest in wormhole physics because this opens a possibility to trip a very large distance in a very short time.In a pioneering work,Morris and Thorne [13]have shown that wormhole geometry could be found from Einstein general theory of relativity.But one has to tolerate the violation of NEC.rahaman@†Dept.of Phys.,Netaji Nagar College for Women,Regent Estate,Kolkata-700092,India.E-Mail:mehedikalam@yahoo.co.inThat means the requirement of matter sources are the same as to explain the recent cosmological state(accelerating phase)of the Universe.For this reason,Wormhole physicists have borrowed exotic matter sources from Cosmologists[14-23].In this article, we will give our attention to Chaplygin gas as a supplier of energy to construct a wormhole. We choose Chaplygin gas as a matter source for the following reasons.In1904,Prof.S. Chaplygin[24]had used matter source that obeys the equation of state as p=−Aρ2is always positive irrespective of matter density(i.e.this is alwayspositive even in the case of exotic matter).In the present investigation,we shall construct some new classes of wormholes in the framework of Chaplygin gas with equation of state p=−A:A static spherically symmetric Lorentzian wormhole can be described by a manifold R2XS2endowed with the general metric in Schwarzschild co-ordinates(t,r,θ,φ)asds2=−eνdt2+eλdr2+r2dΩ22(1) Here,νr]−1(2)where b(r)is shape function.The radial coordinate runs from r0to infinity,where the minimum value r0corresponds to the radius of the throat of the wormhole.Since,we are interested to investigate Chaplygin wormhole,so our wormhole spacetime will never asymptoticallyflat,in other words,we are compelled to consider a’cut off’of the stress energy tensor at a junction interface,say,at r=a.Using the Einsteinfield equations Gµν=8πTµν,in orthonormal reference frame(with c=G=1),we obtain the following stress energy scenario,e−λ −1r +1r2+γ′r2=8πp(4)12(γ′)2−1r=8πp(5)where p(r)=radial pressure=tangential pressure(i.e.pressures are isotropic)andρis the matter energy density.[‘′’refers to differentiation with respect to radial coordinate.]The conservation of stress energy tensor[T b a];b=0implies,dp2(6) Since our source is charaterized by Chaplygin gas,we assume the equation of state asp=−A1+Ee−ν(8) where E is an integration constant.Plugging equation(2)in(3)to yieldρ(r)=b′Since the shape function b(r)satisfies flaring out condition at the throat (i.e.b ′(r 0)<1),then one can have the following restriction asA <1A(12)for all rǫ[r 0,a ].Toy models of wormholesr 3)(13)where constant E is the same as in equation(8).[This function is asymptotically well behaved and always non zero finite for all r >0.So the choice is justified.]E = 222.533.54Exp(nu)12345DistanceFigure 1:The variation of redshift function with respect to rFor the above redshift function (12),we get an expression for ρasρ=A (r 3+1)2(14)By using (9),one can obtain the shape function asA = .00010.00720.00740.00760.00780.008rho(r)12345DistanceFigure 2:The variation of ρwith respect to rb (r )=4π√3[√A2r 6+3r 3+1+2r 3+3rdoes not tend to zero as r →∞i.e.the spacetime is not asymptoticallyA = .000101234567b(r)12345DistanceFigure 3:The variation of shape function with respect to rflat as expected for any Chaplygin wormhole spacetime.Here the throat occurs at r =r 0for which b (r 0)=r 0i.e.r 0=4π√3[ A 2r 60+3r 30+1+2r 30+3r<1when r >r 0.A = .0001–0.1–0.0500.05G(r)0.020.040.060.080.10.120.140.160.180.2rFigure 4:Throat occurs where G(r)cuts r axisNow we match the interior wormhole metric to the exterior Schwarzschild metric .To match the interior to the exterior,we impose the continuity of the metric coefficients,g µν,across a surface,S ,i.e.g µν(int )|S =g µν(ext )|S .[This condition is not sufficient to different space times.However,for space times with a good deal of symmetry (here,spherical symmetry ),one can use directly the field equations to match [30-31]]The wormhole metric is continuous from the throat,r =r 0to a finite distance r =a .Now we impose the continuity of g tt and g rr ,g tt (int )|S =g tt (ext )|S g rr (int )|S =g rr (ext )|Sat r =a [i.e.on the surface S ]since g θθand g φφare already continuous.The continuity of the metric then gives generallye νint (a )=e νext (a )and g rr (int )(a )=g rr (ext )(a ).Hence one can finde ν=(1−2GMa=(1−2GMEquation (16)implies a 3(E −1)+2GMa 2+E =0Thus matching occurs at a =S +T −a 1Q 3+R 2]1Q 3+R 2]19,R =−27a 3−2a 31E −1,a 3=EA2(S +T −a 13)3+1]+2π√3ln[3)6+3(S +T −a 13)3+3A 2a 6+3a 3+1A2ln[2√2a 6+3a 3+1+4a 3+3]+4π√3√2−2π√√2Specialization two :Consider the specific form of shape function asb (r )=d tanh Cr(19)where d and C (>0)are arbitrary constants.We will now verify the above particular choice of the shape function would represent wormhole structure.One can easily that b (r )r<1when r >r 0.d =2, C = 31.21.41.61.82b(r)0.511.522.53DistanceFigure 5:Diagram of the shape function of the wormholed =2, C = 3–1–0.500.51G(r)1 1.52 2.53DistanceFigure 6:Throat occurs where G(r)cuts r axisFor this shape function,the energy density and redshift function will take the following forms asρ=dC64Aπ2r 4cosh 4(Cr )−d 2A 2(21)As the violation of NEC implies ρ2<A ,we see that e νis regular in [r 0,a ],where ′a ′is the cut offradius.d = 2, C =300.00050.0010.00150.002rho(r)1 1.2 1.4 1.6 1.82 2.2 2.4 2.6 2.83DistanceFigure 7:The variation of ρwith respect to rA = .01, d = 2, C = 3, E = 21e–072e–073e–074e–075e–07Exp(nu)1.61.822.2 2.4 2.62.83DistanceFigure 8:The variation of redshift function with respect to rSince the wormhole metric is continuous from the throat r=r0to afinite distance r=a, one can use the continuity of the metric coefficients across a surface,as above,i.e,at′a′. Here we note that the matching occurs at′a′where′a′satisfies the following equationαa5−βa4−γ−δ=0(22) whereα=64π2A,β=128π2GMA,γ=d2(1−4G2M2)2(A2+E2C2)andδ=2GMd2A2(1−4G2M2)2.For this case,the total amount of ANEC violating matter in the spacetime with a cut offof the strees energy at′a′is given byI total=ddC (a510)+12C2(a3cosh2Ca−r30cosh2Cr0)−34C3(a2sinh2Ca−r2sinh2Cr0)+3r )(1−Br→0as r→∞and throat occurs at r0for which D(1−F r0)=r0. The graph indicates the points r0where G(r)≡b(r)=r cuts the’r’axis(seefig.10).Also from the graph,one can see that when r>r0,G(r)<0i.e.b(r)8πr4[(F+B)−2F Br]2r]2(25)As above,the violation of NEC reflects that eνis regular in[r0,a],where′a′is the cut offradius.D = 2, B = .2, F = .3 1.71.751.81.851.9b(r)345678910Distance Figure 9:Diagram of the shape function of the wormhole D = 2, B = .2, F = .3 –1.2–1–0.8–0.6–0.4–0.2G(r)11.522.53r Figure 10:Throat occurs where G(r)cuts r axis D=2, B=.2, F=.30.00020.00040.00060.0008rho(r)45678910r Figure 11:The variation of ρwith respect to rD=2, B=.2, F=.3, E =2, A =.10.010.020.030.040.05exp(nu)468101214Distance Figure 12:The variation of redshift function with respect to rNow this interior wormhole metric will match with exterior Schwarzschild metric at ′a ′where ′a ′satisfies the following system of consistent equations2GM =D (1−Fa )(26)1−2GM a ]2a ]2(27)For this specific wormhole model,the total amount ANEC violating matter in the space-time with a cut offof the stress energy at ′a ′isI total =8DF B (1r 20)−D (F +B )a −17Dα(a 7−r 70)−32π2Aβ5Dα3(a 5−r 50)32π2Aβ33Dα8[(αa +β)3−(αr 0+β)3]−96π2Aβ5Dα8[(αa +β)−(αr 0+β)]−32π2Aβ7Final Remarks2b(r))does not exist forfirst model but for thesecond and third models do exist and take the values’d’and’D’respectively.In spite of these wormholes are supported by the exotic matter characterized by Chaplygin equation of state,but asymptotic mass is positive.This implies for an observer sitting at large distance could not distinguish the gravitational nature between Wormhole and a compact mass’M’.AcknowledgmentsF.R is thankful to DST,Government of India for providingfinancial support.MK has been partially supported by UGC,Government of India under MRP scheme. 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