老托福听力1~2原文及翻译
托福听力tpo50 lecture1、2、3、4 原文+题目+答案+译文
托福听力tpo50 lecture1、2、3、4 原文+题目+答案+译文Lecture1 (1)原文 (1)题目 (4)答案 (6)译文 (6)Lecture2 (8)原文 (8)题目 (10)答案 (12)译文 (12)Lecture3 (14)原文 (14)题目 (16)答案 (18)译文 (18)Lecture4 (20)原文 (20)题目 (22)答案 (24)译文 (24)Lecture1原文NARRATOR: Listen to part of a lecture in an ancient history class.FEMALE PROFESSOR: OK, last time we were discussing trade and commerce during the Bronze Age … And I said a little over 3,000 years ago there was quite a lively trade among the countries along the Mediterranean Sea—people were making objects out of bronze, and they were using bronze tools to make other goods, and they developed trade networks to trade these goods with other countries around the Mediterranean … One of the things they traded was glass …And recently there was an archeological excavation in Egypt—on the Nile River, around where it enters the Mediterranean Sea—where they discovered an ancient glass factory. Robert?MALE STUDENT: I thought our textbook said that the Egyptians imported their glass from other countries.FEMALE PROFESSOR: Well, until now that's what the evidence seemed to suggest. I mean, we had some evidence that suggested that the Egyptians were making glass objects, uh, but not glass.MALE STUDENT: OK, am-am I missing something? They're making glass, but they're not making glass.FEMALE PROFESSOR: I said they were making glass objects, right? You see, it was previously thought that they weren't actually making the raw glass itself, that they were importing unfinished glass from Mesopotamia—um, which today is a region consisting of Iraq, and parts of Syria, Turkey, and Iran—and simply reworking it. Most archeologists believed that the glass factories were in Mesopotamia because that's where the oldest known glass remains come from. You see, there were two stages of glassmaking: the primary production stage, where they made disks of raw glass… Uh, an- and then there was the secondary stage, where they melted the raw glass, the glass disks, and created decorative objects or whatever.And from this new Egyptian site we've learned that the primary production stage had several steps. First, they took quartz—a colorless, transparent mineral—and crushed it. Then they took that crushed quartz and mixed it with plant ash; uh, “plant ash” is just what it soundslike—the ash that's left after you've burned plant material. They slowly heated this mixture, at a relatively low temperature, in small vessels, um containers, like jars, made out of clay. Uh, and that yielded a kind of glassy material…They took this glassy material and ground it up into a powder, and then they used metallic dye to color it… After that, they poured the colored powder out into disk-shaped molds and heated it up to very high temperatures, so that it melted. After it cooled, they'd break the molds, and inside…there were the glass disks. These disks were shipped off to other sites within Egypt and places around the Mediterranean. Then, in the secondary phase, the disks were reheated and shaped into decorative objects. Susan?FEMALE STUDENT: So what kind of objects were people making back then? FEMALE PROFESSOR: Well, the most common objects we’ve found—mostly in Egypt and Mesopotamia—uh, the most common objects were beads; one thing Egyptians were very, very good at was imitating precious stones; they created some beads that looked so much like emeralds and pearls that it was very difficult to distinguish them from the real thing. Uh, and-and also beautiful vessels, uh, with narrow necks; they were probably really valuable, so they wouldn't have been used to hold cooking oil or common food items; they were most likely used for expensive liquids like perfume. Now the glass made at this factory was mostly red; to get this red color, they used copper; in a sophisticated process. Of course, any kind of glass was very valuable, so these red bottles would only have been owned by wealthy people. In fact, because it was so difficult to make, and sort of mysterious and complicated, it was probably a product produced for the royal family, and they probably used glass to show their power. Also, beautiful, expensive objects make great gifts if you're looking to establish or strengthen political alliances…and it's quite possible that ancient Egyptians were actually exporting glass, not just making it or importing it. The trade with Mesopotamia was probably a friendly, mutual trade…because, uh, Mesopotamian glass was usually white or yellow, so Mesopotamians might have said something like, “We'll give you two white disks for two red disks.” There’s no proof ofthat, uh—at least not yet…题目1.What is the lecture mainly about?A. New information about glass production and use in ancient EgyptB. Whether Egyptians or Mesopotamians were the first to invent glassC. Differences between Egyptian glass and other kinds of glassD. Reasons why ancient Egyptians imported glass from other countries2.What is the importance of the archaeological evidence recently found in Egypt?A. It supports the theory that ancient Egyptians imported glass from Mesopotamia.B. It proves that ancient Egyptians made glass objects prior to the Bronze Age.C. It provides the first evidence that glassmaking in the Bronze Age required two different stages.D. It shows that ancient Egyptians were producing raw glass.3.The professor describes a process for making glass disks. Summarize the process by putting the steps in the correct order. [Click on a sentence. Then drag it to the space where it belongs. The last one is done for you.]A.Glass-like material is ground up and dyed blue or red.B.Powdered material is heated at very high temperatures.C.Crushed quartz and plant ash are heated at low temperatures.D.Containers are broken to remove glass disks.4.Based on the lecture, what are two kinds of glass objects that were valued in ancient Egypt and Mesopotamia? [Click on 2 answers.]A. BeadsB. Cooking utensilsC. ContainersD. Windows5.According to the professor, what are two reasons why ancient Egyptians exported glass? [Click on 2 answers.]A. To build relationships with foreign leadersB. To hold cooking oil that was sold in other countriesC. To get bronze tools from other countriesD. To acquire colors of glass not made in Egypt6.Why does the professor say this:Robert: Ok. Am……Am I missing something? They are making glass but they are not making glass?Professor: I said they were making glass objects, right?A. To emphasize that glass objects were only made in ancient EgyptB. To find out what the student does not understandC. To indicate that there was no contradiction in her previous statementD. To correct what she said in her previous statement答案A D CABD AC AD C译文旁白：请听一个古代历史课上的讲座片段。
老托福听力1~2原文及翻译
1Community service【社区服务】is an important component of education here at our university.在我们大学这里，社区服务是教育的一个重要组成部分。
We encourage all students to volunteer for at least one community activity before they graduate.我们鼓励所有的学生在他们毕业前至少志愿参加一次社区活动。
A new community program called "One On One"【一对一】helps elementary students who've fallen behind.一个新的社区计划，叫做“一对一”，帮助落后的小学生You education majors might be especially interested in it because it offers the opportunity to do some teaching—that is, tutoring in math and English.你们教育专业的可能对此很感兴趣，因为它提供了教学的机会，也就是说，辅导数学和英语You'd have to volunteer two hours a week for one semester. You can choose to help a child with math, English, or both.你们必须在一学期内每周志愿服务两个小时。
你可以选择帮助一个孩子的数学、英语或两个都帮。
Half-hour lessons are fine, so you could do a half hour of each subject two days a week.半个小时的课程就好，所以你可以每项做半个小时, 一周做两天。
托福听力tpo40 lecture1、2、3、4 原文+题目+答案+译文
托福听力tpo40lecture1、2、3、4原文+题目+答案+译文Lecture1 (2)原文 (2)题目 (4)答案 (5)译文 (6)Lecture2 (7)原文 (7)题目 (9)答案 (11)译文 (11)Lecture3 (13)原文 (13)题目 (16)答案 (18)译文 (18)Lecture4 (20)原文 (20)题目 (22)答案 (24)译文 (24)Lecture1原文NARRATOR:Listen to part of a lecture in an art history class.MALE PROFESSOR:Last class I passed out your assignment for your first paper,and today I want to spend some time going over it.Mm…most people never take any art history until they get to college,so many of you have probably never written an art history paper before.I gave you a list of appropriate works of art for you to write about.So your next step in this process needs to be to go look at the work you've selected as your topic.And bring a pencil and a notepad with you,because I don't mean you should just drop by at the museum and glance at it so you can say you've seen it in real life.You need to go and sit in front of the work and really look at it—carefully and slowly.And keep careful notes about what you see—you’ll need them for the kind of art history paper you're going to be writing…it's what we call a formal analysis.A formal analysis of a work of art,any kind of art,is based on its formal qualities, which means qualities related to the form—things like color…texture…line…shapes…proportion…and composition.Probably the closest thing to a formal analysis you might have written is for an English class.If you've…say…written an analysis of a poem,you've used the same skills—you've given an analysis of the poem by describing and analyzing its form and meter.A formal analysis paper in art history is very similar.Now,before you begin writing your formal analysis,you'll want to start with a summary of the overall appearance of the work—a brief description of what you see. Are there figures—people?What are they doing?Or is it a landscape…or an abstract representation of something?Tell what the subject is,and what aspects are emphasized in the painting.This will give your reader an overview of what the work looks like before you analyze it.The next part of your paper—the actual formal analysis—will be the longest and most important section of your paper,where you describe and analyze individual design elements.For this portion of the paper,you're going to rely on the notes you took at the museum,because you should be able to describe in detail the design elements the artist uses,and how they are used.For example,does the artist use harsh lines or soft lines—are the colors bright or muted?Focus on the design elements that you feel are most strongly represented in that particular work of art. And if you don't know where to begin,take note of where your eye goes first.Then describe things in the order in which your eye moves around the work.This will help you understand how one part relates to another—the interaction between the different parts of the work.OK,this kind of analysis should occur throughout the main portion of the paper.In the last section of your paper—and this goes beyond formal analysis—you comment on the significance of what you have seen.What details of the work convey meaning?Some significant details will not be apparent to you right away,but if you look long enough,you realize how important they are for your interpretation of the work.Many years ago,I was writing a formal analysis of a painting of a little boy.In the painting,a little boy was standing in his nursery,and he was holding a toy bird in his hand,and there were more toys around him in the background of the painting. Because of the bird he was holding,I assumed at first that the painting was about the innocence of children.But as I looked at the painting longer,I realized that the boy's eyes looked sad even though there was no discernable expression on his face.And then it dawned on me that,even though he was surrounded by toys,he was all alone in his nursery.The boy's eyes were a significant detail in the painting,that I didn't notice at first.题目1.What point does the professor make about the writing of a formal analysis in art history?A.Its objective is to identify common features of several works of art.B.Its most important part is the explanation of an artwork's significance.C.Several styles of writing a formal analysis are used by art historians.D.A particular approach is required to present Information about an artwork.2.According to the professor,what will students need to do before writing the art history paper?A.Look at examples of formal analysis in textbooksB.Take notes on the artwork they will write aboutC.Go to different museums before selecting a topic for the paperD.Study the historical context of the artwork they will write about3.Why does the professor mention an English class?A.To explain the difference between visual language and written languageB.To explain that students need good writing skills for their assignmentC.To point out similarities between a poetry paper and the students'assignmentD.To point out that many art historians become writers4.What does the professor recommend as a way to understand the relationship between different parts of an artwork?A.Looking for lines that connect different parts of the workB.Examining the artwork from several different anglesC.Looking for similar colors the artist used throughout the workD.Determining how the viewer's eyes move around the work5.Why does the professor talk about his own experience analyzing the painting of a little boy?A.To point out a common misconception about formal analysisB.To stress the importance of looking at an artwork thoroughlyC.To show why a formal analysis should not emphasize small detailsD.To provide an example of an artwork that is easy to analyze6.The professor describes three sections the art history paper should contain.Place them in the order in which they should appear in the paper.Click on a phrase.Then drag it to the space where it belongs.A.Analysis of the design elements the artist usesB.Discussion of the meaning of the artworkC.Summary of the appearance of the artwork答案D B C D B CAB译文旁白：下面听一段艺术史课程的片段。
托福听力tpo46 lecture1、2、3、4 原文+题目+答案+译文
托福听力tpo46lecture1、2、3、4原文+题目+答案+译文Lecture1 (2)原文 (2)题目 (4)答案 (6)译文 (6)Lecture2 (8)原文 (8)题目 (10)答案 (12)译文 (12)Lecture3 (14)原文 (14)题目 (16)答案 (18)译文 (18)Lecture4 (19)原文 (19)题目 (22)答案 (24)译文 (24)Lecture1原文NARRATOR:Listen to part of a lecture in a biology class.FEMALE PROFESSOR:I'd like to continue our discussion of animal behavior and start off today's class by focusing on a concept we haven't yet touched upon—swarm intelligence.Swarm intelligence is a collective behavior that emerges from a group of animals,like a colony of termites,a school of fish,or a flock of birds.Let's first consider the principles behind swarm intelligence,and we'll use the ant as our model.Now,an ant on its own is not that smart.When you have a group of ants,however, there you have efficiency in action.You see,there's no leader running an ant colony. Each individual,each individual ant operates by instinctively following a simple set of rules when foraging for food.Rule number1:Deposit a chemical marker…called a pheromone.And rule2:Follow the strongest pheromone path.The strongest pheromone path is advantageous to ants seeking food.So,for example,when ants leave the nest,they deposit a pheromone trail along the route they take.If they find food,they return to the nest on the same path and the pheromone trail gets stronger—it's doubled in strength.Because an ant that took a shorter path returns first,its pheromone trail is stronger,and other ants will follow it, according to rule2.And as more ants travel that path,the pheromone trail gets even stronger.So,what's happening here?Each ant follows two very basic rules,and each ant acts on information it finds in its immediate local environment.And it's important to note: Even though none of the individual ants is aware of the bigger plan,they collectively choose the shortest path between the nest and a food source because it's the most reinforced path.By the way,a-a few of you have asked me about the relevance of what we're studying to everyday life.And swarm intelligence offers several good examples of how concepts in biology can be applied to other fields.Well,businesses have been able to use this approach of following simple rules when designing complex systems,for instance,in telephone networks.When a call is placed from one city to another,it has to connect through a number of nodes along the way.At each point,a decision has to be made:Which direction does the call go from here?Well,a computer program was developed to answer this question based on rules that are similar to the ones that ants use to find food.Remember,individual ants deposit pheromones,and they follow the path that is most reinforced.Now,in the phone network,a computer monitors the connection speed of each path, and identifies the paths that are currently the fastest—the least crowded parts of the network.And this information,converted into a numeric code,is deposited at the network nodes.This reinforces the paths that are least crowded at the moment. The rule the telephone network follows is to always select the path that is most reinforced.So,similar to the ant's behavior,at each intermediate node,the call follows the path that is most reinforced.This leads to an outcome which is beneficial to the network as a whole,and calls get through faster.But getting back to animal behavior,another example of swarm intelligence is the way flocks of birds are able to fly together so cohesively.How do they coordinate their movements and know where they're supposed to be?Well,it basically boils down to three rules that each bird seems to follow.Rule1:Stay close to nearby birds.Rule2:Avoid collision with nearby birds.And rule3:Move in the average speed and direction of nearby birds.Oh,and by the way,if you're wondering how this approach can be of practical use for humans:The movie industry had been trying to create computer-generated flocks of birds in movie scenes.The question was how to do it easily on a large scale?A researcher used these threerules in a computer graphics program,and it worked!There have also been attempts to create computer-generated crowds of people using this bird flocking model of swarm intelligence.However,I'm not surprised that more research is needed.The three rules I mentioned might be great for bird simulations,but they don't take into account the complexity and unpredictability of human behavior.So,if you want to create crowds of people in a realistic way,that computer model might be too limited.题目1.What is the lecture mainly about?A.Various methods that ants use to locate foodB.A collective behavior common to humans and animalsC.A type of animal behavior and its application by humansD.Strategies that flocks of birds use to stay in formation2.According to the professor,what behavior plays an important role in the way ants obtain food?A.Ants usually take a different path when they return to their nest.B.Ants leave chemical trails when they are outside the nest.C.Small groups of ants search in different locations.D.Ants leave pieces of food along the path as markers.3.What are two principles of swarm intelligence based on the ant example?[Click on2answers.]A.Individuals are aware of the group goal.B.Individuals act on information in their local environment.C.Individuals follow a leader's guidance.D.Individuals instinctively follow a set of rules.4.According to the professor,what path is followed by both telephone calls on a network and ants seeking food?A.The path with the least amount of activityB.The most crowded pathC.The path that is most reinforcedD.The path that has intermediate stopping points5.Why does the professor mention movies?A.To identify movie scenes with computer-simulated flocks of birdsB.To identify a good source of information about swarm intelligenceC.To emphasize how difficult it still is to simulate bird flightD.To explain that some special effects in movies are based on swarm intelligence6.What is the professor's attitude about attempts to create computer-generated crowds of people?A.She believes that the rules of birds'flocking behavior do not apply to group behavior in humans.B.She thinks that crowd scenes could be improved by using the behavior of ant colonies as a model.C.She is surprised by how realistic the computer-generated crowds are.D.She is impressed that computer graphics can create such a wide range of emotions.答案C B BD C D A译文下面听一段生物学讲座的片段。
托福听力tpo39 lecture1、2、3、4 原文+题目+答案+译文
托福听力tpo39lecture1、2、3、4原文+题目+答案+译文Lecture1 (2)原文 (2)题目 (4)答案 (6)译文 (6)Lecture2 (8)原文 (8)题目 (10)答案 (12)译文 (12)Lecture3 (14)原文 (14)题目 (16)答案 (18)译文 (18)Lecture4 (19)原文 (19)题目 (22)答案 (23)译文 (24)Lecture1原文NARRATOR:Listen to part of a lecture in a geology class.MALE PROFESSOR:Since Earth formed,some four and a half billion years ago,the number of minerals here has increased dramatically,from a few dozen relatively simple minerals early on…to over4,300kinds of minerals we can identify today—many of them wonderfully complex.A basic question of geology is how all these new minerals came into being.Well,recent studies have turned to biology to try to explain how this happens.Now,much of biology is studied through the lens of evolution.And the theory of evolution suggests that,as environments change—and inevitably they do—some organisms will have characteristics that allow them to adapt to those changes successfully…characteristics that help these organisms develop and survive and reproduce.And when environments become more complex—as tends to happen over time—those earlier adaptations,those variations…become the basis of yet other combinations and variations…and lead to ever more diverse and complex forms of life.So from fewer,simpler,and relatively similar forms of life billions of years ago,life on Earth has now become a dazzling array of diversity and complexity.Well,some geologists now want to apply this concept to explain mineral diversity too. The conditions that minerals are under are not constant.Conditions like temperature or pressure or chemical surroundings—these change—often in cycles,increasing and decreasing slowly over time.And as conditions change,minerals sometimes break down and their atoms recombine into totally new compounds,as part of a process some call mineral evolution.Now,minerals are not alive,of course,so this is not evolution in quite the same sense you'd have in living organisms.But there do appear to be some parallels.Living organisms not only adapt to their environment but also affect it—change theenvironment within which other organisms may then develop.Likewise,each new mineral also enriches the chemical environment from which lots of other,even more complex new minerals may be formed in the future.Beyond these similarities,though,what's really fascinating about mineral evolution is the way minerals apparently coevolve with living organisms.Uh,what do I mean by that?Well,it's maybe a billion years after Earth’s formation that we first see evidence of life.Of course,early life-forms were primitive—just tiny,single-celled microbes—but over time,they had a profound effect.Huge numbers of these microbes began producing food by photosynthesis,which,of course,also freed up enormous amounts of oxygen.And lots of that oxygen interacted with the atoms of existing minerals,creating rust out of iron,for instance,…reacting with a whole range of different metals to create lots of new minerals.Now,living organisms rely on minerals.But they not only take in some minerals as nutrients,they also excrete others as waste products...including what we call biominerals—minerals that form with the help of biological life.We can see geologic evidence of biomineral production in what are called stromatolites.Stromatolites look like wavy layers of sedimentary rock.But they're really fossils—fossils of the waste from microbial mats.Microbial mats are vast colonies of one-celled organisms…that were once the most prevalent form of life on Earth.And the study of stromatolites indicates that these ancient microbial mats interacted with minerals in the environment and left behind new compounds as waste products—biominerals like carbonates,phosphates,and silica.In fact,we’ve grown microbial mats in the laboratory,and,over time,they too have produced some of the same sorts of minerals found in stromatolites.Uh,you don't need to know the details of the process right now—we’re still figuring out just how it works,ourselves.But you might be interested to know that this concept of mineral evolution is being used in the search for evidence of life on other planets.The thinking is that if certainminerals occur here on Earth as a result of a biological process,and if we also find those same minerals on another planet,…this would suggest that life may have once existed there.But—just because a particular mineral is found on say,Mars or Venus—uh,we really shouldn't assume that whatever caused it to turn up there…must be the same process that formed that mineral here on Earth.题目1.What is the main purpose of the lecture?A.To explain how geologists identified the minerals present during Earth's formation.B.To explain why living organisms require certain minerals to survive.C.To explain the differences between simple and compound minerals.D.To explain a recent theory about mineral formation.2.What point does the professor make about the minerals present during Earth's formation?A.They were comparatively few of them.B.They were more complex than minerals formed on other planets.C.Most were not affected by temperature and pressure changes on early Earth.D.Some of them are no longer being formed naturally on Earth.3.What similarities does the professor point out between minerals and living organisms?[Click on2answers.]A.Both first appeared on Earth at approximately the same time.B.They both can be formed only in the presence of oxygen.C.They both have become more diverse and complex over time.D.Not only are they both shaped by their environment,but both also affect it.4.What are stromatolites?A.Fossils remains of microbial mats.yered deposits of iron-based minerals.yers of rock that indicate changes in Earth's pressure and temperature.D.Rock formations created when oxygen interacts with certain metals.5.Why does the professor talk about microbial mats?A.To explain why organisms tend to colonize near certain minerals.B.To describe how minerals can be created by living organisms.C.To illustrate the effects of geological processes on living organisms.D.To emphasize that evolving life depended on the presence of oxygen.6.What does the professor think about using evidence of minerals on another planet to determine whether life has existed there?A.He believes it is the most promising way to search for life on another planet.B.He doubts that complex minerals will ever be found on another planet.C.He is cautious about assuming that certain minerals indicate the presence of life.D.He is surprised that the technique was not suggested until recently.答案D A CD A B C译文旁白：请听一段地质学讲座的节选片段。
托福听力tpo66 lecture1、2、3 原文+题目+答案+译文
托福听力tpo66lecture1、2、3原文+题目+答案+译文Lecture1 (1)原文 (1)题目 (3)答案 (5)译文 (5)Lecture2 (7)原文 (7)题目 (9)答案 (11)译文 (11)Lecture3 (13)原文 (13)题目 (15)答案 (17)译文 (18)Lecture1原文Professor:OK,today,I want to talk about sleep.We all sleep.Human sleep,many animal sleep.When we sleep,we aren't actually unconscious,but in a state of reduced awareness of our surroundings.Now,what does that mean for animals in the wild,if they are in a state like that?Unable to monitor their environment?Male Student:Well,they're helpless,vulnerable to predators,maybe.Professor:Right.They are vulnerable to predators.Yeah,they sleep.So let's talk about why,the biology of sleep.So the first thing l want you to understand is that sleeps a very risky behavior.And risky don't evolve unless they bring the animals some kind of benefit that outweighs that risk.So sleep must have a really important function.And I want to emphasize that there is a difference between sleep and other forms of inactivity,like regular rest.The insects,for instance,rest.But they don't sleep.What's specific to sleep is thatthe brain alters many of its usual activities,including its connection to sensory and motor organs,it shuts those connections down.So a sleeping animal can usually neither sense nor move.And I say usually because…well,we will get to that in a minute.So,basically all mammals and birds sleep.But there are some unusual ways of sleeping.Take marine mammals.Like dolphins,dolphins need to swim up for air once in a while,so they can't completely shut off all movement and sensation.So their brain can't shut down completely.But dolphins get around this.How?won't they sleep one brain hemisphere at a time?Sleeping dolphins actually look like they're just resting,awake and occasionally swim up for air.So how can we even tell their sleeping?Well,we measured their brain activity which showed that1/2was active while the other was sleeping.That's some adaptation, uh?So,what is the function of sleep?As I said,it must be important,but why?Okay.I know you're all tempted to say,uh,that sleeps when the whole body rests that sleep is our mechanism to recover from physical activity.And it's true.When you sleep, your muscles lose their tone,they relax,the body saves energy.But this could happen even during regular waking rest.I mean,that's probably what happens when insects rest.You don't need sleep for that.You can get the same benefit by resting awake.So this doesn't explain why sleep involved.To explain the real function,the most important benefit of sleep.You'll need to focus on the brain,not the muscles.Remember how we can tell that a dolphin sleeping not just resting,is because of a unique pattern of brain activity,which is a clue that sleeps function has to do specifically with the brain.And that's the general consensus cause,that's what could explain by it evolved.It also explains why sleep is a characteristic of mammals and birds,because they have the most complex brains of all animals.The simpler brain uh like a reptile gets by with little sleep or even without sleep.OK,so we know that sleep benefits the brain but in what way?We are notsure yet.Okay.So one hypothesis is that during sleep,the brain's synthesize molecules that it needs for proper functioning when awake.The longer we stay awake,the more those molecules get depleted.So the brain needs to replenish them,and this supposedly happens during sleep.I'm talking about energy sources like glycogen and some types of neuro-transmitter that are needed to transmit signals between nerve cells.So these get replenish during sleep and the next morning our brain is working with a full supply of energy and neuro-transmitters again.With that explains why we feel so alert and mentally refreshed after night sleep.Yes,Jim?Male Student:Well,you know,I don't work well in the morning at all.Female Student:Yeah,I do my best work at night too.Professor:Not everyone's at their best in the morning.I grant you that.But that doesn't rule out the replenishment hypothesis.It's just a bit more complicated than I said.They were fairly sure that there's this other rhythm of mental activity going on that independent of sleep.It's like a pre-program24hours cycle.Your mental activity peaks at a certain hour every day,like at night,for you two.And then it goes down at some other point.But the point is that after a sleepless night,that peak is not as high as it would normally be,and the longer you go without,the lower those peaks get. So the replenishment may be needed to keep the metal high.Does that make sense? The two mechanisms are not mutually exclusive.That's what I'm trying to say.题目1.What is the main purpose of the lecture?A.To explain why people sleep at night rather than during the dayB.To discuss the problems caused by a lack of sleepC.To explain why muscles in the body need sleepD.To explore benefits that are provided by sleep but not by regular rest2.Why does the professor mention that sleep is a risky behavior?A.To suggest that resting while awake is better than sleepingB.To indicate how important the benefits of sleep must beC.To explain why many animals sleep during the dayD.To explain why birds sleep less than mammals3.According to the professor,why is the sleep of dolphins unusual?A.Their sleep is interrupted whenever they need to come up for air.B.They can move around while they are asleep.C.In every dolphin group only half of the dolphins are asleep at any given time.D.Their brains show no activity during sleep.4.What does the professor conclude about the view that the main function of sleep is to allow the body to recover from physical activity?A.It is true for all animals except marine mammals.B.It is supported by measurements of brain activity.C.It explains why sleep has evolved.D.It is not convincing when examined more closely.5.According to the hypotheses discussed by the professor,what determines howalert we feel at a particular time of the day?[Click on2answers.]A.The supply of certain chemicals in our brainB.The chemical composition of our dietC.Our24-hour cycle of mental activityD.The time of day when we usually wake up6.Why do the students say this:Male Student:Well,you know,I don't work well in the morning at all.Female Student:Yeah,I do my best work at night too.A.To show the professor that they have understood the theoryB.To support the professor's point that people tend to be active at the same timeC.To point out a fact that seems to contradict the hypothesis the professor just discussedD.To indicate that they would like to change their sleeping habits答案D B B D AC C译文教授：好的，今天我想谈谈睡眠。
托福听力tpo63 lecture1、2、3 原文+题目+答案+译文
托福听力tpo63lecture1、2、3原文+题目+答案+译文Lecture1 (1)原文 (1)题目 (3)答案 (5)译文 (5)Lecture2 (7)原文 (7)题目 (9)答案 (11)译文 (11)Lecture3 (13)原文 (13)题目 (15)答案 (17)译文 (17)Lecture1原文Listen to part of a lecture in a geology class.Professor:OK.Before we begin,I wanna remind you that our field trip to Bryce canyon national park is this weekend.Remember the bus leaves early,five am,so don't forget to set your alarm clocks.I think you're all gonna enjoy getting out of the classroom and actually seeing some remarkable geologic phenomena.Now,while we're there,I want you to pay particular attention to two things.One obviously will be the sediment layers making up the rocks,since we've spent so much time onsedimentary rocks.Bryce canyon is a great place to see how millions of years have turned layers and layers of tightly packed sediment,mud particles,sand remains of plants and animals into rock.But you're also gonna see some fascinating rock shapes, formations that are the result of the weathering and the erosion processes that occur at Bryce canyon.There are two main processes that are important.The first one is a weathering process called frost wedge.Frost wedge a process that widens cracks in rocks in the wintertime.It begins with warm air or daytime sun melting the snow.As the snow turns into water,it seeps into the cracks that occur naturally in sedimentary rocks.At night,this water freezes in the cracks,but when water freezes,it expands quite a bit, which means that it prize cracks open,gradually,making them wider and breaking off a little bits in the process.Now,this thought freeze cycle can happen as many as two hundred times in a single year.So that makes it the most important weathering process at Bryce canyon.The other key processes is runoff,which is an erosion process.Runoff takes place in the summer.The parks in the desert said the grounds very dry.When it rains in late summer,the ground is too hard to absorb the water,so it runs off.And as it runs off, it carries away the gravel,the broken bits of rock created by cross wedge in the winter.So runoff is the main erosion process that alters the rock landscape in the park.And because these processes have occurred over thousands of years,some of the results can be pretty dramatic,like the giant corridors are passage ways that have developed within the rocks.These passage ways are known as slot canyons.Here's an example of one,not from the part we're going to.This one is actually in Australia,but the scale is typical.So these huge spaces started out as small cracks throughout the sedimentary rock,then thanks to millions of cycles across wedge and runoff.What used to be one big area of rock is now sort of two smaller areas of brought with the corridor in between.We'll have a chance to walk through some like this.These slot canyons are great places to explore,but let me just say,for any of you who aren't from around here,if you ever go on your own,make sure you check aweather forecast first.A sudden heavy rain can cause a flash flood in a slot canyon. So you want to know when it's safe to explore them.Unfortunately,it'll be dry this weekend.Now,these deep,narrow slots are pretty common.You might even have two of them very close to each other with only a thin wall of rock in between.Of course,frost wedge is still at work,so it starts wearing away at the front of the thin wall until you get a whole I mean a hole all the way through the wall,front to back.And this hole gets bigger and bigger.Once it's at least one meter in diameter,it's called a window.And eventually the weight on top of it is just too much,so the roof caves in and only the sides,sometimes it's just one side is left standing.These sides,which look a lot like collins,now are called Hudos.Here's a photo of something we'll be seeing.One of the things that makes Bryce canyon unique is that it has more Hudos than anywhere else in the world.Yes,Margot?Female student:Why is it so lumpy looking?You'd think it would be smoother.Professor:Well,remember,these are sedimentary rocks,so they have layers.Some layers are mostly limestone,and limestone erodes pretty quickly in the presence of any kind of acid.Now Bryce canyon in a very unpolluted area,but even,there the rain water has a little carbolic acid in it,which causes the limestone to erode.But other layers are made up of different types of sediment,which aren't so vulnerable to acid,so they don't erode as quickly.题目1.What is the lecture mainly about?A.The length of time required to produce sedimentary rocksB.The role of climate conditions in the creation of sedimentary rocksC.Some processes that produced a specific group of rock formationsD.Some unique geologic features found in canyons in the United States2.According to the professor,what is one characteristic that frost wedging and runoff share?A.Neither occurs in a desert.B.Neither is a frequent event.C.Both are weathering processes.D.Both are seasonal phenomena.3.Why does the professor show a picture of a slot canyon?A.To give students a sense of the size of a typical slot canyonB.To show students one of the places they will visit on their field tripC.To illustrate how many sediment layers are visible in a typical slot canyonD.To show how much slot canyons can vary based on local climate conditions4.What is the professor's attitude toward students exploring Bryce Canyon on their own?A.He worries that students may not know to take appropriate precautions if they go by themselves.B.He suspects that many students will not go on their own if such a trip requires them to get up early.C.He hopes that the class field trip will motivate students to visit Bryce Canyon on their own.D.He believes that students learn more from individual exploration than they dofrom being in a group.5.How is a hoodoo formed?A.Runoff produces large gravel deposits.B.Air pollution leads to a buildup of limestone.C.The roof of a rock window collapses.D.A flash flood washes away the base of a rock wall.6.According to the professor,what two factors explain why a hoodoo does not have a smooth shape?[Click on2answers.]A.The presence of acid in rainwaterB.The temperature swings between the summer and the winter seasonsC.The composition of the hoodoo's sedimentary layersD.The location of the cracks created by frost wedging答案C D A A C AC译文听一段地质学的讲座。
托福听力tpo64 lecture1、2、3 原文+题目+答案+译文
托福听力tpo64lecture1、2、3原文+题目+答案+译文Lecture1 (1)原文 (1)题目 (3)答案 (5)译文 (5)Lecture2 (7)原文 (7)题目 (9)答案 (11)译文 (11)Lecture3 (13)原文 (13)题目 (15)答案 (17)译文 (17)Lecture1原文Listen to part of a lecture in an economics class.The professor has been talking about international trade.Professor:OK,so let's recap from yesterday.Why do nations engaged in international trade?Well,it's often because of a surplus,more than they need,and they also trade for the opposite reason when they have shortages and can't produce everything they want or need domestically.So these explanations are good as far as they go.But there's another scenario we need to discuss.And that is what if a country is capable of producing something it wants or needs but it can also import the same product from another country?Now,how does the country decide whether to make the product itself or import it?OK,take an example.Um,think about the bananas that you buy in the supermarket.If you look closely,you'll see that most bananas in the United States are imported,imported from countries with tropical climates.But theUnited States has warm regions.It has greenhouse.Clearly,it would be possible to grow bananas here.So why doesn't the US do that?Scott?Student Scott:Well,it is like a lot cheaper and more efficient for countries with tropical climates,for tropical countries to grown bananas,isn't it?I mean,they don't need greenhouse to grow bananas,and they're not so limited to certain regions.Professor:Okay,good.That's exactly right.Tropical countries have what we call an absolute advantage in producing bananas.Absolute advantage is the term we use when a country can produce more of a product using fewer resources.They're the most efficient producer of something.And the United States can't be that with bananas.So it's better off specializing in other goods that it can make more efficiently.Let's take an example,say we have two countries and say they each make only two products and they trade only with each other.Simplistic I know.But well, you'll see where I'm going with this in a moment.OK,so as I was saying,two countries,two products,one country can produce both products more efficiently than the other country.Should these two countries even trade at all?Student Scott:Uh,well,no,I mean,like what's in it for the more efficient country?Professor:Well,what is in it for them?Let's,um,well,let's call these countries um,X and Y.Country X makes both TVs and chairs more efficiently than country Y does.It has an absolute advantage in producing both commodities?No question.But what economists also look at is relative efficiency.And from that perspective,we see that country X is a lot more efficient at making TVs than it is at making chairs and in country Y,ah,well,it turns out they're more efficient at making chairs than TVs.So we say that country Y has a comparative advantage at chair making.And country X has a comparative advantage at TV making.So what should happen?Well,first,both countries should specialize in the production of just one thing.The product they're most efficient at making.Country X should make only TVs and country Y should make only chairs,then two of them should trade.Specialization and trade are going to lead to increase in production and increased overall supply of goods and generally lowerprices.Right?Student Scott:Professor,I still don't see how countries figure out when and where they have a comparative advantage.Professor:Well,you can't fully understand the concept of comparative advantage without also considering the related concept of opportunity cost.Opportunity cost is what you lose,uh,the options you have to give up in order to use your time and resources for something else,countries can determine where their comparative advantages lies,uh,like making TVs instead of chairs by figuring out what they can make with the lowest opportunity cost.Ah,you know,maybe this will be clear if we apply it on a personal level.Now think about when you go out to a movie,your direct monetary cost is the price of the movie ticket.Right?But you also spend two hours at the theater.Your opportunity cost includes both,uh,whatever else you could have spent your money on.Um,ten candy bars may be and whatever else you could have accomplished during the time you were watching the movies,uh,you might have completed your homework for this class,or you might have work two hours overtime at your job,thereby earning instead of spending money.See,these lost possibilities are your opportunity cost.题目1.What is the lecture mainly about?A.Advantages that countries can gain by making their own goodsB.Inequalities that lead to trade imbalances between countriesC.Cost and efficiency concepts that help determine trade decisionsD.Ways in which local surpluses can affect international trade2.Why does the professor talk about growing bananas in countries with tropicalclimates?A.To show how opportunity costs affect agricultural productionB.To explain how demand for a product determines its costC.To describe how domestic shortages are createdD.To illustrate the concept of absolute advantage3.According to the professor,what indicates that a country has an absolute advantage in trade?A.It can produce an item more efficiently than other countries.B.It is wealthy enough to import everything that it needs.C.It consistently exports more than it imports.D.It does not have to import any goods from other countries.4.The professor gives an example of two countries that produce televisions and chairs. What does she predict will happen if the economic decisions of both countries are based on the principle of comparative advantage?[Click on2answers.]A.The prices of televisions and chairs will go down in both countries.B.More chairs and televisions will be manufactured in each country.C.Imports of televisions and chairs will decrease in each country.D.The total supply of televisions and chairs will increase in both countries.5.Why does the professor talk about going to the movies?A.To demonstrate the difference between absolute and comparative advantageB.To provide an example to help explain the concept of opportunity costsC.To illustrate the advantages of specialization in the entertainment industryD.To show that economic theories do not always apply on a personal level6.Why does the professor say this:say we have two countries and say they each make only two products and they trade only with each other.Simplistic I know.But well,you'll see where I'm going with this in a moment.A.To reassure the students that the example will help illustrate her pointB.To apologize to the students for using an example that is difficult to understandC.To prepare the class for a shift to a new topicD.To return to a point she made earlier答案C D A AD B A译文请听经济学课上的部分内容。
托福听力tpo51 lecture1、2、3、4 原文+题目+答案+译文
托福听力tpo51lecture1、2、3、4原文+题目+答案+译文Lecture1 (1)原文 (1)题目 (3)答案 (5)译文 (6)Lecture2 (7)原文 (7)题目 (10)答案 (12)译文 (12)Lecture3 (14)原文 (14)题目 (16)答案 (18)译文 (18)Lecture4 (20)原文 (20)题目 (22)答案 (24)译文 (24)Lecture1原文NARRATOR:Listen to part of a lecture in a botany class.FEMALE PROFESSOR:So,continuing with crop domestication,and corn—or,um, maize,as it's often called.Obviously it's one of the world's most important cropstoday.It's such a big part of the diet in so many countries,and it's got so many different uses,that it's hard to imagine a world without it.But because it doesn't grow naturally,without human cultivation,and because there's no obvious wild relative of maize…uh,well,for the longest time,researchers weren’t able to find any clear link between maize and other living plants.And that's made it hard for them to trace the history of maize.Now,scientific theories about the origins of maize first started coming out in the 1930s.One involved a plant called teosinte.Teosinte is a tall grass that grows wild in certain parts of Mexico and Guatemala.When researchers first started looking at wild teosinte plants,they thought there was a chance that the two plants—um, maize and teosinte—were related.The young wild teosinte plant looks a lot like the corn plant,and the plants continue to resemble each other—at least superficially—even when they're developed.But when the scientists examined the fruits of the two plants,it was a different story. When you look at ripe corn,you see row upon row of juicy kernels…um,all those tiny little yellow squares that people eat.Fully grown teosinte,on the other hand, has a skinny stalk that holds only a dozen or so kernels behind a hard,um,almost stonelike casing.In fact,based on the appearance of its fruit,teosinte was initially considered to be a closer relative to rice than to maize.But there was one geneticist,named George Beadle,who didn't give up so easily on the idea that teosinte might be…well…the“parent”of corn.While still a student in the1930s,Beadle actually found that the two plants had very similar chromosomes—very similar genetic information.In fact,he was even able to make fertile hybrids between the two plants.In hybridization,you remember,the genes of two species of plants are mixed to produce a new,third plant—a hybrid.And if this offspring—this hybrid—is fertile,then that suggests that the two species are closely related genetically.This new,hybrid plant looked like an intermediate,right between maize and teosinte.So,Beadle concluded that maize must've been developed over many years,uh,that it is a domesticated form of teosinte.Many experts in thescientific community,however,remained unconvinced by his conclusions.They believed that,with so many apparent differences between the two plants,it would have been unlikely that ancient—that prehistoric peoples could’ve domesticated maize from teosinte.I mean,when you think about it,these people lived in small groups,and they had to be on the move constantly as the seasons changed.So for them to selectively breed,to have the patience to be able to pick out just the right plants…and gradually—over generations—separate out the durable,nutritious maize plant from the brittle teosinte that easily broke apart…it's a pretty impressive feat,and you can easily see why so many experts would have been skeptical.But,as it turns out,Beadle found even more evidence for his theory when he continued his experiments,producing new hybrids,to investigate the genetic relationship between teosinte and maize.Through these successive experiments,he calculated that only about five specific genes were responsible for the main differences between teosinte and maize—the plants were otherwise surprisingly similar genetically.And more recently,botanists have used modern DNA testing to scan plant samples collected from throughout the Western Hemisphere.This has allowed them to pinpoint where the domestication of maize most likely took place—and their research took them to a particular river valley in southern Mexico.They've also been able to estimate that the domestication of maize most likely occurred about9,000 years ago.And subsequent archaeological digs have confirmed this estimate.In one site,archaeologists uncovered a set of tools that were nearly9,000years old.And these tools were covered with a dusty residue…a residue of maize,as it turns out…thus making them the oldest physical evidence of maize that we've found so far.题目1.What is the lecture mainly about?A.A research study that compares wild and domesticated plantsB.Problems with a commonly held hypothesis about the origin of teosinteC.Reasons why wild plants are usually unsuitable for agricultureD.The process used to identify the ancestor of a modern crop2.What evidence seemed to indicate that maize and teosinte are not related?A.Young teosinte plants do not physically resemble young maize plants.B.Preliminary DNA evidence indicated that teosinte was related to rice.C.Maize and teosinte usually grow in significantly different climates.D.Maize and teosinte have very different types of kernels.3.Why does the professor discuss hybrids?A.To explain how a geneticist confirmed that maize was widely grown9,000years agoB.To indicate the earliest method used by geneticists to identify plant originsC.To explain a method used to demonstrate a link between two plant speciesD.To describe how geneticists distinguish between wild plants and domesticated plants4.What was most researchers'initial view of George Beadle's theory about teosinte?A.They accepted it but questioned the evidence cited.B.They rejected it because of conflicting archaeological evidence.C.They questioned it because it implies that ancient farmers were sophisticatedplant breeders.D.They questioned it because genetic research was viewed with skepticism at that time.5.What did Beadle conclude about maize and teosinte?A.Both plants lack particular genes that are common in most domesticated plants.B.Both plants have particular genes that enable them to adapt to varying climates.C.Only a small number of genes are responsible for the differences between the two plants.D.The genetic composition of both plants is very similar to that of rice.6.According to the professor,why was the discovery of stone tools important?A.It proved that teosinte was simultaneously domesticated in multiple locations.B.It helped to confirm the period in which maize was first domesticated.C.It suggested that maize required farming techniques that were more complex than experts had previously assumed.D.It provided evidence that maize plants were used for more purposes than experts had previously assumed.答案D D C C C B译文旁白：请听一段植物学讲座的节选。
托福听力tpo67 lecture1、2、3 原文+题目+答案+译文
托福听力tpo67lecture1、2、3原文+题目+答案+译文Lecture1 (2)原文 (2)题目 (4)答案 (6)译文 (6)Lecture2 (7)原文 (7)题目 (10)答案 (12)译文 (12)Lecture3 (13)原文 (14)题目 (16)答案 (18)译文 (18)Lecture1原文Professor:Now we've said that animal behavior patterns involve an interplay between an animal and its environment.In particular,behavior patterns can change as an animal becomes adapted to its environment.We can see the results of this in the way that animals have developed different types of feeding behavior.Animals are generally classified as a generalist feeders and specialist feeders.Now,um,these terms are used in a variety of ways.At times,they're used to refer to an animal's range of habitats.I've also seen them used to describe the number of foraging techniques that are used by an individual or species.Um,but for our purposes,we're going to use them to refer to the range of food items that are eaten by a species.So a generalist feeder is a species that eats a wide variety of foods during its lifetime.And a specialist is a species that feeds on a highly restricted number of foods.A good example of a generalist would be a rat.Rats are notorious for eating just about anything that's available,whether it's a plant or an animal.At the other end of the spectrum,we have the koala which eats only the leaves of eucalyptus trees.Okay,now there are advantages to each.For a generalist,If1type of food isn't around,it can feed on another that's more abundant.On the other hand,the advantage of being a specialist is that the animal is well adapted to its food.You could say that specialists are feeding masters,their consumption,even their digestive system is just so finely tuned.For instance,take the koala.The eucalyptus leaves that it feeds on,don't contain much protein.What's more,the leaves contain compounds that are poisonous to most species?But the koalas digestive system has adapted to handle this.It's liver deactivates,the poisonous compounds,and its digestive system is designed to extract the maximum amount of nutrients from the leaves.So it's not a question of which strategy is better.The real question is,what determines how selective animal species are in what they eat?Well,the answer maylie in a concept called optimal foraging.The idea is that natural selection favors animals whose feeding behavior has the lowest cost to benefit ratio.That is you want to get the best healthiest food you can.And you want to do it as quickly as possible. And as easily as possible.Now,in a natural environment,no animal forage in an absolutely optimal manner. But,well,I read some research on a little rat called the kangaroo rat,which lives in deserts in North America.The kangaroo rat is a generalist which eats plant matter like seeds and fruit.It lives in deep burrows which provide protection from the desert heat and from predators like hawks or snakes.And it goes foraging at night for food.For plant matter,under the protection of darkness,even though it's a generalist.If the only thing available is seed,if a choice of seeds is available to it,it picks up seeds that provide more energy than those it leaves behind.And it carries them back to its burrow.Once it's there,it might eat only the richest seeds from the ones that brought back.So it selects seeds outside in a way that lets it spend as little time as possible foraging in that risky environment,and then sorts out its food later when it's safely in its burrow.Oh,yes,Kenneth.You have a question?Male student:But what about the koala?It gets by uh,by being even more selective, you'd think you would be really risky to rely completely on eucalyptus leaves. Wouldn't it be better to diversify like the kangaroo rat,and eat,at least one or two other things?Professor:Well,what do you think the koala would say?What do I gain by being so selective?In terms of optimal foraging,it's clear that eucalyptus trees provide an abundant source of food.Other animals can't eat the leaves and think of how little energy the koala uses.It spends only about3hours each day eating to get the energy it needs.So being a specialist allows it to get the nutrients it needs with minimal expenditure of energy.题目1.What is the lecture mainly about?A.The reasons why some animals eat only plantsB.The advantages of two different feeding adaptationsC.The variety of foods that certain animals can eatD.The relationship between two animals that share a habitat2.What definition of the term“generalist”does the professor use in the lecture?A.An animal species that eats a wide variety of foodsB.An animal species that lives in a range of different habitatsC.An animal species that uses several techniques to forage for foodD.An animal species that forages at several different times of the day3.What points does the professor make about the koala’s specialist feeding habits? [Click on2answers.]A.It obtains all the food it needs in relatively little time.B.It requires large amounts of protein in its diet.C.It can eat leaves that are poisonous to other animals.D.It spends most of its time eating.4.What does the professor imply about the kangaroo rat?A.It will take more risks when foraging for high-energy food.B.It is one of the most selective feeders in North America.C.Its competitors often eat its food supply.D.It is selective when choosing what food it eats.5.How does the professor organize the information in the lecture?A.By contrasting an old theory with a new theoryB.By defining important terms and then giving examples of themC.By describing the similarities between two animalsD.By describing a problem and then suggesting some solutions6.Why does the professor say this:Male student:But what about the koala?It gets by uh,by being even more selective, you'd think you would be really risky to rely completely on eucalyptus leaves. Wouldn't it be better to diversify like the kangaroo rat,and eat,at least one or two other things?Professor:Well,what do you think the koala would say?What do I gain by being so selective?In terms of optimal foraging,it's clear that eucalyptus trees provide an abundant source of food.Other animals can't eat the leaves and think of how little energy the koala uses.A.To express agreement that the koala should eat a greater variety of foodB.To indicate that the koala’s behavior does not illustrate optimal foragingC.To remind the man of the characteristics of selective feedersD.To encourage the man to consider the koala’s feeding behavior differently答案B A ACD B D译文我们已经说过动物的行为模式涉及到动物和它的环境之间的相互作用。
托福听力tpo60 lecture1、2、3 原文+题目+答案+译文
托福听力tpo60 lecture1、2、3 原文+题目+答案+译文Lecture1 (1)原文 (1)题目 (3)答案 (5)译文 (5)Lecture2 (7)原文 (7)题目 (9)答案 (11)译文 (12)Lecture3 (13)原文 (13)题目 (16)答案 (18)译文 (18)Lecture1原文Listen to part of a lecture in an art history class.As you know, artists today can choose from an enormous selection of media, including water colors, acrylic paints, not to mention special pains formulated for almost any surface you might wanna paint on. But even so, oil paints are still the medium of choice among most professional artists and hobbyists. So why is that? well, for one thing, oil paints extremely versatile, suitable for many different painting styles, different subjects, and different sizes of work. Another advantage is thatthey're easy to use. Even for beginners, they can be manipulated. You can apply oil paint to a canvas. And then because they don't dry right away, they can be scraped off and paint it over.So you don't have to waste expensive material every time you make a change. Unlike acrylic paint, which really can't be moved once it's applied, acrylic paints dry very quickly. So in general, when using them, it's more difficult to make changes. And with watercolors, you can't really paint over a mistake, because it really diminishes the freshness of the colors. So oil paint is the medium of choice for many painters. Nowadays, anyway, in terms of art history, oil paints actually pretty young in Europe before the invention, rather, the development of oil paint, painters mostly used Tempera. Tempera was made with egg yolk. Believe it or not, the yoke acted as a binder. A binder enables the color pigment to stick to your canvas, and no temporal wasn't always yellow. If that's what you're thinking. Artists made their own paint by mixing egg yolk with a color pigment like powdered iron ore copper. But it dried very fast, which left little room for error or change.You really had to get it right the first time. Then in the early 15th century, a Flemish painter named Jan of Van Eyck started experimenting up after that emperor in one of the Nikes paintings cracked while drawing in the sun. He decided to try to make a paint that would avoid this fate. So he tried. And oil mixture, actually other painters before him had tried using oils as a binder. So while the Nikes credited with inventing oil paint, it's not entirely true. In Greece and Italy, olive oil had been used to prepare pigment mixtures, but the paint took a really long time to dry, just the opposite of tempera. But van Eyck had a secret recipe for his oil paint. He used linseed oil. Not only did this paint dry without cracking, van dyke also discovered that it could be applied in very thin layers. This technique gave the colors of depth that was previously unknown. And just as important, the linseed oil actually increased the brilliance of the color. So as a result, pigment oil mixtures became very popular among artists. Some tried to improve the paint by developing their own recipes, like uh, by using walnut oil, for instance, or by cooking their oil mixtures. But a greatmany began using some sort of oil as their binder.Now with all this experimentation with mixtures, well, it took a long time for artists to get comfortable with using these new oil paints to get a true feeling for how to apply them to the best effect. The early painters in oil like that Ike laid the paint down in thin layers with brush strokes that were so delicate that they're practically invisible. And it really wasn't until the end of the 16th century and in the 17th century that the full potential of oil paint was realized, for example, that's when artists finally began to combine delicately painted areas with thick brush strokes. So you could actually see the marks of the brush combining the rough and the smooth gives oil paintings great textural depth. Of course, the public who are used to smooth surfaces actually complained that these paintings looked unfinished. And some of that attitude carried over until later centuries, like, well, you're probably familiar with the work of the painter Vincent Van Gogh. Van gogh's famous nowadays for his thick, swirling brush strokes. But amazingly enough, his work was not appreciated back in the 19th century, and he sold just one painting during his lifetime. Of course, the French impressionists, who were his contemporaries, attained more popular acclaim, but they used a different technique. They applied oil paint and thick dabbs to depict the effects of light on the landscape.题目1.What does the professor mainly discuss?A. The relationship between painting techniques and types of paint that are usedB. Reasons for the changes in the popularity of oil paint since the seventeenth centuryC. The historical development and use of oil paintD. The main differences between oil paint and tempera2.What reasons does the professor give for the popularity of oil paint among modern artists?[Click on 2 answers.]A. It can be used for a number of painting styles.B. It allows artists to make changes.C. It does not fade easily.D. It can be made easily even by amateur painters.3.What property do tempera and acrylic paint have in common?A. They do not stick well to the canvas.B. They tend to crack as they dry.C. They tend to make colors look dull.D. They dry very quickly.4.What are two points the professor makes about the painter Jan van Eyck?[Click on 2 answers.]A. He did not invent the use of oil as a binder.B. He improved his own oil mixtures by heating them.C. He invented tempera.D. He applied oil paint to a canvas in thin layers.5.Why does the professor talk about combining delicate brushstrokes with thickbrushstrokes?A. To explain the popularity of van Eyck's paintingsB. To describe a difference between linseed oil and olive oil as a binderC. To indicate that artists became more experienced in the use of oil paintD. To point out a similarity between the painters van Eyck and van Gogh6.Why does the professor mention Vincent van Gogh?A. To emphasize that paintings made with thick brushstrokes were unpopular in the pastB. To show that artists did not know how to use oil paints correctly until the nineteenth centuryC. To describe the origin of a painting technique used by the French ImpressionistsD. To support his statement about when painters first began to use thick brushstrokes答案C ABD AD C A译文请听艺术史课上的部分内容。
托福听力tpo49 lecture1、2、3、4 原文+题目+答案+译文
托福听力tpo49lecture1、2、3、4原文+题目+答案+译文Lecture1 (1)原文 (1)题目 (4)答案 (6)译文 (6)Lecture2 (8)原文 (8)题目 (10)答案 (12)译文 (12)Lecture3 (14)原文 (14)题目 (17)答案 (19)译文 (19)Lecture4 (21)原文 (21)题目 (23)答案 (25)译文 (25)Lecture1原文NARRATOR:Listen to part of a lecture in a geology class.MALE PROFESSOR:Alaska is fascinating to geologists because of its incrediblelandscapes.Uh,permafrost has a lot to do with this.That is,the areas where the ground—the soil—is always frozen,except for the very top layer—what we call the active layer of permafrost—which melts in the summer and refreezes again in the winter.The northern part of Alaska is covered in lakes—thousands of them—and most of these are what we call thaw lakes.T-h-a-w.Thaw lakes.I'm gonna show you a few sketches of them in a minute,so you'll have a good idea of what I'm talking about.So, how these thaw lakes are formed has to do with…OK,it starts with ice wedges.The top part of the ice wedge melts—Should I back up?Ice wedges form when water runs into cracks in the ground,the permafrost,then freezes.You ever see mud after it dries?Dried mud has cracks,because when it dries, it contracts,it shrinks.Well,in winter,permafrost behaves similarly.It shrinks in winter,because it freezes even more thoroughly then,and as it shrinks,it forms deep,deep cracks.Then in the summer,when the active layer—the top layer of the permafrost—melts,the melt water runs into those cracks in the permafrost,then freezes again—because that ground,the ground beneath the active layer,is still below freezing.So,you have wedges of ice in the permafrost.Now the ice wedges widen the original cracks in the permafrost,because water expands when it freezes.All right?OK,then in autumn,the active layer on top freezes again.Then in winter,the permafrost starts contracting again and the cracks open up even wider.So the next summer,when the active layer melts again and flows into the widened cracks…and…freezes…it makes the cracks even wider.So it’s sort of a cycle through which the cracks and the wedges grow wider and wider.So when the ice wedge reaches a certain size,its top part—in the active layer—turns into a little pond when it melts in the summer.And that's the beginning of your thaw lake.[pause]There are thousands of them in northern Alaska.One of the most fascinating things about these lakes—and this is important—is that they mostly havethe same shape.Like an elongated oval,or egg shape.And what's more,all the ovals are oriented in the same way.Here's an idea of what they look like,what the landscape looks like from an aerial view,with the lakes side by side.There's been considerable research done to try to figure out what causes them to be shaped and oriented this way.We know that the shape and orientation are caused by the way the lakes grow once they're formed,but the question is,what makes them grow this way?One theory sees winds as the cause.This region of Alaska has strong winds that blow perpendicular to the lakes.What happens is,wind blows straight into the longer side of the lakes.Now,wouldn’t that erode the lake bank in that direction?The same direction as the wind?Well…no.Actually,what happens is that the waves caused by the winds build a sorta protective layer of sediment—it's called a“protective shelf”—along the bank of the lake directly in front of them;so that bank is shielded from erosion,and the waves are diverted to the sides,to the left and to the right,and that’s why the left and the right banks start eroding.Get it?The bank straight ahead is protected,but the lake currents--the waves--erode the banks to the sides.That's the current model,um,the wind erosion model,which is generally accepted.But,there's a new theory that says that[deliberately]thaw slumping,not wind,is what shapes the thaw lakes.Thaw slumping,um…OK.Sometimes,in the summer,the temperature rises pretty quickly.So the active layer of permafrost thaws faster than the water can drain from the soil.So the sides of the thaw lakes get,like,mushy,and slump,or slide,into the lake.Then,the lake water spreads out more,and the lake gets bigger,OK?Also,in that part of Alaska,the terrain is gently sloped,so the lakes are all on an incline.Here.Now,this is an exaggeration of the angle—the hill isn't this steep—butsee how with the lake's banks,the side that is farther downhill…it's smaller,lower. This short bank thaws faster than the tall one does,so it falls into the lake—it slumps, much more and much faster than the other bank.When the short banks of many lakes slump,they move farther downhill and the lakes grow—all in the same downhill direction.This is a new theory,so it hasn't been tested much yet.In field studies,when we've looked at the banks of these thaw lakes,there's not much evidence of slumping. We'd expect to see cliff-like formations there,from the slumping,but we haven't really found many of those.题目1.What is the main purpose of the lecture?[Click on two answers.]A.To contrast how different kinds of thaw lakes growB.To explain why a new theory of thaw lakes is gaining acceptanceC.To explain how processes in permafrost lead to the formation of thaw lakesD.To describe two competing theories about the growth of thaw lakes2.The professor explains thaw lake formation as a cycle of events that occur repeatedly.Summarize this cycle,starting with the event filled in below.[Click on a sentence.Then drag it to the space where it belongs.The first one is done for you. One sentence will not be used]A.Meltwater flows into cracks in permafrostB.Ice wedges inside permafrost completely meltC.Freezing water expands cracks in permafrostD.Ice in the active layer melts as temperatures riseE.Permafrost shrinks and cracks as temperatures drop..3.What is the significance of the'protective shelf'discussed by the professor?A.It prevents the slumping of lake banks.B.It shields the lake surface from strong winds.C.It redirects the waves to lake banks that do not face the wind.D.It allows the lakes to grow in the same direction as the wind blows.4.According to the thaw slumping model,which side of a thaw lake grows fastest?A.The side where the bank is shortestB.The side least exposed to windC.The side that is at the highest elevationD.The side opposite the protective shelf5.What is the professor's opinion of the thaw slumping model?A.He thinks it was urgently needed.B.He is not convinced that it has a firm basis.C.He thinks it would be better if it were simplified.D.He does not think it is very different from the old model.6.Why does the professor say this:You ever see mud after it dries?A.He wants some information from the students.B.He thinks that the students may find an example helpful.C.He realizes that he forgot to mention an important topic.D.He wants to point out an important difference between frozen ground and dry ground.答案CD EDACB C A B B译文听一段地质学的讲座。
托福听力tpo41 lecture1、2、3、4 原文+题目+答案+译文
托福听力tpo41lecture1、2、3、4原文+题目+答案+译文Lecture1 (2)原文 (2)题目 (4)答案 (5)译文 (6)Lecture2 (7)原文 (7)题目 (9)答案 (11)译文 (12)Lecture3 (13)原文 (13)题目 (16)答案 (18)译文 (18)Lecture4 (20)原文 (20)题目 (22)答案 (24)译文 (24)Lecture1原文FEMALE PROFESSOR:Many organisms have developed the ability to survive in harsh environmental conditions—extreme heat or cold,or,very dry conditions....Like, plants in the desert—your textbook doesn’t have much about the specifics on desert plants,but I think that desert plants are great examples of specialized adaptations to extreme environmental conditions.So with desert plants,there are basically three different adaptive strategies.And I should point out that these strategies are not specific to any particular species—many different species have developed each of the adaptations.So,first off,there are succulent plants.There are many different species of succulent plants,but they all can absorb and store a lot of water.Obviously,opportunities to get water in the desert are few and far between.Generally,rains are light and short,so the rain doesn’t seep too far down into the soil…and there's a limited window of time for any plant to get the water before it evaporates.But succulent plants have a spread-out and shallow root system that can quickly pull in water from the top inch of soil,though the soil has to be saturated,since succulents aren't good at absorbing water from soil that’s only a little moist.Succulent plants also are well suited to retaining water—important in an environment where rainy days are rare.Succulent plants can store water in their leaves,in their stems,or in their roots.And to keep that moisture from evaporating in the hot desert sun,most succulent plants have a waxy outer layer that makes them almost waterproof when their stomates are closed.They also preserve water by minimizing their surface area—the more of the plantthat’s out in the sun,the more potential there is to lose stored-up water—and that means that most succulent plants have few,if any,leaves.Now besides succulent plants,there are also drought-tolerant plants. Drought-tolerant plants are like bears in a way.You know how bears mostly sleep through the winter?They can survive without eating because their metabolism slows down.Well,drought-tolerant plants also go into a dormant state when resources—in their case,water—runs short.A drought-tolerant plant can actually dry out without dying.I said before that most desert rains are light and brief,but occasionally there's a heavy one.Drought-tolerant plants revive after one of these significant rainfalls—and they're able to absorb a good bit of the rainfall due to their deep roots.Actually the root system for drought-tolerant plants is more extensive than the root systems of many plants that live in wetter climates.Drought-tolerant plants can even absorb water from relatively dry soil because of their deep roots,in contrast to succulent plants.The third adaptive strategy is to avoid the drought conditions altogether.Yes,there are plants that do this—annual plants.An annual plant will mature and produce seeds in a single season that will become the next generation of annual plants.In desert conditions,annual plants grow in the fall or spring to avoid the heat of summer and the cold of winter.Of course,these plants could face a serious problem if a particular fall or spring happened to be very dry—they would have difficulty growing and could die before producing seeds.But they have a mechanism to prevent one year of low rainfall from wiping them out. Not all seeds an annual plant puts out will grow the following year.Some seeds remain dormant in the ground for several years.It's a type of insurance that protects the annual plants from a season of poor growing conditions,of unfavorable weather.题目1.What is the lecture mainly about?A.The growth rates of plants in different geographical regionsB.Different ways that plants have adapted to desert environmentsC.The different mechanisms that plant roots use to absorb waterD.Different kinds of succulent plants2.What are two features of succulent plants that help them survive in deserts?[Click on2answers.]A.Succulent plants store water in their leaves and stems.B.Succulent plants become dormant until the next rainfall.C.Succulent plants have short stems.D.Succulent plants have few leaves.3.Why does the professor mention bears?A.To remind students of information from a previous lectureB.To point out a feature common to all desert plantsC.To reinforce a point about drought-tolerant plantsD.To help students understand the concept of adaptation4.What is one ability that drought-tolerant plants have that succulent plants do not have?A.The ability to absorb water from dry soilB.The ability to absorb water through their leavesC.The ability to prevent moisture from being lost through their leavesD.The ability to shed leaves5.Why can annual plants grow in a desert even after a year of no rainfall?A.Annual plants have an extensive root system that can absorb water from far away.B.Annual plants produce seeds all year long.C.Seeds of annual plants can store water for a long time.D.Seeds of annual plants can survive in the ground for a long time without water.5.Listen again to part of the lecture.Then,answer the question.(PROFESSOR)The third adaptive strategy is to avoid the drought conditions altogether.Yes,there are plants that do this.Why does the professor say this: (PROFESSOR)Yes,there are plants that do this.A.To correct a previous statementB.To acknowledge a potentially surprising factC.To anticipate the types of questions that students might have about the topicD.To make sure that students are paying attention答案B ADC AD B译文教授：许多生物已经发展了在恶劣环境中生存的能力：酷热、严寒，或者非常干燥的环境。
托福听力tpo61 lecture1、2、3 原文+题目+答案+译文
托福听力tpo61lecture1、2、3原文+题目+答案+译文Lecture1 (1)原文 (1)题目 (3)答案 (5)译文 (5)Lecture2 (7)原文 (7)题目 (9)答案 (11)译文 (11)Lecture3 (13)原文 (13)题目 (15)答案 (17)译文 (17)Lecture1原文Listen to part of a lecture in a sociology class.Sociology is really a cross disciplinary field.We find that elements of biology, psychology,and other sciences often overlap as we study particular phenomena.So let me introduce a concept from cognitive psychology.Okay,let's say someone asks you to look at a list and memorize as many items on it as you can.Most of us are able to remember,on average,seven items.There are several variations of this memory test.And the results consistently show that the human limit for short term memoryis seven bits of Information.This limit is called channel capacity.Channel capacity is the amount of information that can be transmitted or received over a specific connection,like our brain and the channel capacity for our short-term memory.It has some interesting real-life implications,like phone numbers.Local numbers here in the United States all have seven digits,because the phone companies realized early on that longer numbers would lead to a lot more wrong numbers being dialed.But the idea of channel capacity doesn't apply just to our cognitive abilities.It also affects our relationships with people around us.Psychologists talk about sympathy groups.These are the people,close friends,family to whom we devote the most time.We call or see them frequently,we think about them,worry about them.And studies show for each of us,the size of that group is about10to15people.But why so small?sure.Relationships take time and emotional energy.And most of us don't have unlimited amounts of either.But what if there's another reason?what if it's our brain that setting the limit?And in fact,there's evidence that indicates that our social channel capacity may actually be a function of our brain size,or more accurately,the size of our neocortex.The neocortex is the frontal region in the brain of mammals that's associated with complex thought.Primates have the largest neocortex is among mammals,but among different primate species,humans,apes,baboons, neocortex size varies.A lot of theories have been proposed for these variations.Like maybe it's related to the use of tools,but no theories ever seemed like a perfect explanation.Until the late1990s,what an anthropologist named Robin Dunbar published an article about his studies of primates.Dunbar theory is that if you look at any particular species of primate,you'll find that if it has a larger neocortex that it lives in a larger social group.Take human beings,we have the largest neocortices and we have the largest number of social relationships.So we've said that our sympathy group is10to15people.What about our other relationships other than family and close friends,such as those that occur in the workplace will call these social groups as opposed to sympathy groups?How many relationships can we handle there?Those relationships aren't as involved,so we can handle more of them.But is there an upper limit?well,Dunbar says that there is,and he developed an equation to calculate it.His equation depends on knowing the ratio between the size of the neocortex and the size of the whole brain.That is of the whole brain,what percentage of it is taken up by the neocortex?Once you know the average percentage for any particular species,the equation predicts the expected maximum social group size for that species.For humans,that number seems to be about150. So according to Dunbar’s equation,our social groups probably won't number more than150people.Now,Dunbar’s hypothesis isn't the kind of thing that's easy to confirm in a controlled experiment,but there is anecdotal evidence to support it.As part of his research,Dunbar reviewed historical records for21different traditional hunter gatherer societies.And those records showed that the average number of people in each village was just under150,148.4to be exact.Dunbar also worked with biologists to see if his hypothesis applies to other mammals besides primates. When they looked at meat eating mammals,carnivores,they found that the ones with a larger neocortex also have a bigger social group.And the number of individuals in that group is predicted by Dunbar’s equation supporting his hypothesis. But when they looked at insectivores,mammals that eat insects,the results were inconsistent.The data didn't disprove Dunbar’s hypothesis,but wasn't a nice,neat match like the carnivore studies,which isn't totally surprising.Insectivores are hard to observe,since many of them only come out at night or they spend a lot of time underground.So,we know a lot less about their social relationships.题目1.What is the lecture mainly about?A.The role that the neocortex plays in human memoryB.The connection between neocortex size and social relationships in mammalsC.Various studies that compare social group sizes in humans and other mammalsD.Ways that humans can expand the size of their social groups2.Why does the professor discuss the length of some telephone numbers?A.To show that real-world applications are informed by cognitive psychologyB.To point out an exception to a well-known principle about memoryC.To explain why telephone numbers are used in tests of memoryD.To explain why people often dial the wrong telephone number3.What does the professor imply about the size of a person's sympathy group?A.It closely matches the size of the person's family.B.It becomes larger when a person learns how to feel compassion for others.C.It may not be something a person makes a conscious decision to control.D.It may not be as predictable as the size of the person's social group.4.What did Dunbar's study of the records of some traditional hunter-gatherer societies indicate?A.Hunter-gatherer societies were the first to form social groups.B.Tool usage by humans is related to social group size.C.There is a maximum social group size for humans.D.Hunter-gatherers tend to have smaller-sized social groups.5.What does the professor say that biologists discovered in their research of animals other than primates?A.Dunbar's hypothesis accurately predicts social group sizes for all animals.B.Social group sizes of carnivores are more difficult to predict than those of insectivores.C.Data on insectivore behavior neither support nor contradict Dunbar's hypothesis.D.The size of an animal's neocortex is affected by its diet.6.Why does the professor say this:But why so small?sure.Relationships take time and emotional energy.And most of us don't have unlimited amounts of either.A.To encourage students to spend more time developing relationshipsB.To emphasize that her point is based on personal experienceC.To indicate that she realizes that the students already know the answer to her questionD.To suggest that there is more than one possible response to her question答案B AC C C D译文请听社会学课上的部分内容。
托福听力tpo43 lecture1、2、3、4 原文+题目+答案+译文
托福听力tpo43lecture1、2、3、4原文+题目+答案+译文Lecture1 (2)原文 (2)题目 (4)答案 (6)译文 (6)Lecture2 (7)原文 (7)题目 (10)答案 (12)译文 (12)Lecture3 (14)原文 (14)题目 (16)答案 (18)译文 (19)Lecture4 (20)原文 (20)题目 (22)答案 (24)译文 (25)Lecture1原文NARRATOR:Listen to part of a lecture in a botany class.FEMALE PROFESSOR:It's autumn,and as you know,in most parts of the United States the leaves on the trees are changing color from green…to yellow,orange,and lots of other colors.So this'll be a great time to talk about how and why some of these leaves turn one color in particular—and that's bright red.Well,before we discuss why leaves turn red,first let's,um—look,I know this is very old material,but just to play it safe—let's first go over why leaves are usually green.It’s chlorophyll, right?Leaves get their green color from chlorophyll—the chemical that's responsible for photosynthesis.The chlorophyll in the leaves collects energy from the Sun,in the form of sunlight,and it converts this energy into sugar,which is food for the plant. It's chlorophyll that makes leaves green most of the time.Now,the classic explanation for why leaves change color is this.In autumn,the leaves start preparing for the winter and stop synthesizing new chlorophyll.Since chlorophyll is sensitive to sunlight and to cold temperatures—both of which you get in autumn—the existing chlorophyll in the leaves breaks down.And since it's not being replaced by the new chlorophyll,the green color of the leaves gradually fades away.As this happens,the other pigments present in the leaf become visible.According to the classic theory,this is true for the red pigment as well.It was there in the leaf all along but it was hidden by the green chlorophyll.OK, so that's the classic explanation,and it's partially right.Why do I say“partially”?Well,it's probably true for pigments like yellow or orange,but it doesn't seem to hold for the red pigment.Let's back up a bit.Just what produces this red color in leaves?It's a red pigment called anthocyanin.Here's where the classic explanation doesn't seem to apply to red.What's interestingis that during the summer,there was very little if any anthocyanin in the leaves,but in the weeks before a tree is about to drop its leaves,the production of anthocyanins increases significantly.In other words,unlike those other pigments,anthocyanins are not just unmasked by the breakdown of chlorophyll in autumn;they're actually created at this time.So that raises a question.Why would a tree produce more anthocyanin just before dropping its leaves?Why does the tree spend so much of its resources doing this just before the leaves fall off?On the surface,this doesn't make sense.It'd be like spending money to,I don't know,to have your old car repainted when you know the car's not going to last more than a couple of months.All this extra anthocyanin in the autumn seems like a waste.But remember,nature is very economical with its resources,so that means anthocyanin must be serving some function that's important for the tree.Today there are some theories about what that function might be.One of them involves predatory insects;another involves fungi.You know,the more I read about these theories and the related research,it always created more questions for me than answers.So I was really glad to learn about a totally different theory…a new one.It seemed to come with research and data that give a full explanation.So here it is.Remember I said the chlorophyll breaks down?Well,in autumn,a whole lot of other chemical constituents of the leaf break down as well.I don't mean they're totally destroyed,'cause actually they break down into other,different chemicals that the tree can reabsorb from the leaves and reuse later.Now,this reabsorption process is very important for the tree,and—here's the key—it's sensitive to light,meaning that too much exposure to sunlight can interfere with this process.So where does anthocyanin fit in here?Well,anthocyanin's more stable than chlorophyll.It's not harmed as easily by the Sun or the cold.So it's still working long after the chlorophyll breaks down.But what doesit do?The theory is that anthocyanin protects the reabsorption process from the sunlight. For example,if you look closely at a red leaf on a tree,you'll notice that most of the red pigment is on the upper side of the leaf,the side facing the Sun.This new theory suggests that what the anthocyanin is doing there on top is shielding the rest of the leaf from the sunlight…and more importantly,allowing those important chemicals to be reabsorbed by the tree.题目1.What is the main purpose of the lecture?A.To explain how the red pigment in leaves breaks downB.To show that leaf color varies based on the tree speciesC.To introduce a theory about why leaves turn a particular colorD.To explain how chlorophyll protects trees in autumn2.What does the professor imply when she explains why leaves are green?A.She wants to correct a common misconception about the topic.B.She thinks the students are probably already familiar with the material.C.She believes the process is too complicated to discuss in depth.D.She knows that students are often confused about the functions of chlorophyll3.What does the professor mean when she says that the classic theory is partially right?A.It describes what happens in the summer but not what happens in autumnB.It describes what happens in tree leaves but not what happens in leaves of other plantsC.It explains how pigments are synthesized but not how they break down.D.It explains some cases of color change in tree leaves but not all cases.4.Why does the professor mention painting a car?A.To question why a large amount of anthocyanin is produced just before leaves fallB.To explain why most leaves turn red instead of other colorsC.To remind students how cooler temperatures affect the color of leavesD.To show how anthocyanin absorbs sunlight to produce food for trees5.The professor mentions theories about why leaves turn red that involve predatory insects and fungi.What is her opinion about those theories?A.They are based on careful research.B.They do not completely explain the phenomenon.C.They have not received enough attention.D.They have been proved to be incorrect.6.According to the professor,why does anthocyanin appear on the upper side of some leaves?A.To help chlorophyll absorb the sunlightB.To maximize the leaf's utilization of sunlightC.To accelerate the breakdown of chlorophyllD.To protect an important process from the sunlight答案C BD A B D译文旁白：请听一部分植物学的讲座。
托福听力tpo53 lecture1、2、3、4 原文+题目+答案+译文
托福听力tpo53lecture1、2、3、4原文+题目+答案+译文Lecture1 (1)原文 (1)题目 (4)答案 (5)译文 (6)Lecture2 (8)原文 (8)题目 (10)答案 (12)译文 (12)Lecture3 (14)原文 (14)题目 (16)答案 (18)译文 (18)Lecture4 (20)原文 (20)题目 (22)答案 (24)译文 (24)Lecture1原文NARRATOR:Listen to part of a lecture in a film studies class.MALE PROFESSOR:Nowadays,we take sound in films for granted—I mean,you stillmight see black and white films occasionally,but you hardly ever see silent films anymore.So it's interesting to note that the use of recorded sound was originally controversial FEMALE STUDENT:What about all the sounds you hear in some silent movies?Like, you know a loud sound when somebody falls down or something?MALE PROFESSOR:OK,you're talking about a soundtrack added much later,which has,over time,become part of the film we know.But this recorded track didn't exist then.And it's not that most people didn't want sound in films;it's just that the technology wasn't available yet.Don't forget that instead of recorded sound there was often live music that accompanied movies in those days—like a piano player or a larger orchestra in the movie theater.Also,think of the stage,the live theater—it has used wonderful sound effects for a long time and,if wanted,these could be produced during the viewing of a film.You know,the rolling of drums for thunder or whatever.But that wasn't as common.Oh,and another thing that they might have in movie theaters in the early days was a group of live actors reading the parts to go along with the film.Or—and this seems a particularly bad idea to us now—one person narrating the action…an early example of a long tradition of movie producers—the ones concerned mostly about making money—not having much confidence in their audience,thinking that people somehow couldn’t follow the events otherwise.So,it finally became possible to play recorded sound as part of the film in the1920s. Trouble was,it wasn't always used to very good effect.First,it was,you know, amazing to see somebody's mouth move at the same time you hear the words…or hear a door close when you see it closing on-screen.But that luster wears off,of course,and if you're a director,a filmmaker,what's the next step?FEMALE STUDENT:Well,use sound to enhance the movie,right?Bring something more to it that wasn't possible…MALE PROFESSOR:Yes,that's exactly what directors who were more interested in cinema as art,not commerce,were thinking.But they also predicted that there would be a problem that sound would be misused, and,boy,was it ever…Because the commercial types,the producers and so on were thinking,OK,now that sound is possible,let's talk as much as possible and forget about the fact that we're making a movie,that we have this powerful visual medium.So,many of the films of the twenties were basically straight adaptations of successful shows from the stage,theater.The name they used for sound films then was"talking films,"and that was on the mark,since,well,all they pretty much did was talk.And talk.So,the remedy?Well,what was proposed by a number of filmmakers and theorists was the creative,expressive use of sound—what they generally called nonsynchronous sound.OK,synchronous sound means basically that what we hear is what we see. Everything on the soundtrack is seen on the screen.And everything was recorded simultaneously,which,well,since the sound technicians working on films often had experience with live radio,that made sense to them.Recording the sound separately and adding it in afterward—well that idea was less obvious.Anyway,synchronous sound means the source of the sound is the image on the screen.Nonsynchronous sound then,is…FEMALE STUDENT:The sound doesn't match the picture?MALE PROFESSOR:Right.Now we can look at this in various ways,but let's take it as literally as possible.Music—unless we see the radio or the orchestra—that's nonsynchronous.If the camera shot is of the listener rather than the speaker,that's nonsynchronous.If wehear,say,background sounds that aren't on the screen—that's nonsynchronous.So,that doesn't seem so radical,does it?But,again,those early producers didn't think their audiences could keep up with this.FEMALE STUDENT:Excuse me,but did you say earlier that some filmmakers actually advocated not using sound at all?MALE PROFESSOR:Well,yes,but that was a bit of an exaggeration,I guess.What I meant to say was that some filmmakers thought that the way the film sound was actually used was setting the art of filmmaking back.But everyone agreed that sound solved some very difficult issues,and offered potentially exciting tools.题目1.What is the lecture mainly about?A.The influence of theater on early sound filmsB.Conflicting views on uses of sound during the early days of sound filmsC.The great progress in cinema after the development of soundD.Viewer reactions to early sound films2.According to the professor,what types of sound were used in silent film theaters? [Click on3answers]A.Live music performed in the theaterB.Sound effects created in the theaterC.Recorded sound tracks played with the filmD.Live narration during the filmE.Musical entertainment offered before the film3.What is the professor's attitude toward early movie producers?A.He is critical of their influence on films.B.He thinks they had little influence on films.C.He thinks they understood what audiences wanted.D.He acknowledges that they made progress possible.4.According to the professor,what was characteristic of sound films in the1920s?A.Dialogues between characters were kept to a minimum.B.Many films were closely based on theater plays.C.Musical sound tracks were added to most films.D.Sounds were recorded separately and added to films later.5.What is an example of synchronous sound in a film?A.A character hearing a train that is not visibleB.A past conversation being replayed in a character's mindC.A character playing guitar and singing on screenD.A song playing at the end of a film as credits appear on the screen答案B ABD A B C译文Narrator：请听一段电影研究讲座的节选。
托福听力tpo58 lecture1、2、3 原文+题目+答案+译文
托福听力tpo58lecture1、2、3原文+题目+答案+译文Lecture1 (1)原文 (1)题目 (4)答案 (6)译文 (6)Lecture2 (8)原文 (8)题目 (10)答案 (12)译文 (12)Lecture3 (14)原文 (14)题目 (16)答案 (18)译文 (19)Lecture1原文NARRATOR:Listen to part of a lecture in a biology class.FEMALE PROFESSOR:So,those are some of the common theories on bird migration. Now let’s talk about“homing.”Homing is more than just the return flight home from migratory trips—homing can take place at any time and from any location.It’s the ability that some birds have of finding their way back to an exact location regardless of their starting point…or how far away they are…or the time of year…and so on. You’ve all heard of homing pigeons but there are lots of bird species that have highlyrefined homing skills so maybe there’s some evolutionary advantage.Why would birds be so good at this?Todd?MALE STUDENT:Well,baby birds stay in the nest while the parents go out and hunt for food.If the parents have to fly all over the place to find the food,they’d need to be able to find the nest again.FEMALE PROFESSOR:And once you’d found food you’d want to get home quickly, wouldn’t you?To feed your young?So you’d want the most direct path home—you wouldn’t want to retrace whatever winding,meandering path you’d taken while you were searching for food.Being able to fly home directly is very efficient:the offspring get food faster and their parents are home sooner to look out for them.MALE STUDENT:But,it isn’t just the offspring that benefit—the adult birds get back to a safe place sooner as well.FEMALE PROFESSOR:Right.Now,what about finding your way home after going south for the winter?FEMALE STUDENT:Well,it’d be nice if you could go back to a place you knew was OK. Ya’know,one that’s got water or food…Not too many predators.Some place where you might even still have a nest.FEMALE PROFESSOR:Good.Now,so far,we’ve been talking about times when birds intentionally—or,at least instinctively—leave home,but are there other reasons why a bird might find itself away from its nest?FEMALE STUDENT:Birds are vulnerable to really strong winds.Storms could blow them pretty far off course.FEMALE PROFESSOR:But finding your way back to your nest when you’ve been accidentally displaced is a little different from getting home after your annual migration to a warmer climate.So,do you think all those mechanisms we discussed…that birds use when migrating…apply to homing as well?FEMALE STUDENT:I think so.I mean we talked about using the Sun and the stars asnavigational guides—and that would certainly be helpful for homing.And so would that ability to sense Earth’s magnetic poles—the one in the studies you described about the,uh,internal magnetic compass birds have.Yeah,it should be the same.FEMALE PROFESSOR:OK,so celestial bodies make good navigational aids.Anything else?MALE STUDENT:Well,for short distances,you could just memorize the e landmarks.Like,when my friend tells me to turn left after I see the post office to get to his house.FEMALE PROFESSOR:So,when birds are out searching for food,they can memorize landmarks.Mountains,rivers…who knows,maybe even the post office.Studies of gannets have shown that this is one way they navigate.Gannets are seabirds so when they wind up in an unfamiliar location over land,they fly in outward spirals until they reach the coast.Then they use the coastline to find their way home.Of course,when we say that birds“memorize”their terrain—that may not be accurate.It’s not always a good idea to use human analogies when trying to understand animal behavior—particularly when it comes to navigation which we,as a species,are spectacularly bad at.I mean,even with maps,how often do we get lost? But,with birds,they’re actually overengineered to be good at navigation.Just think about all those tools we’ve discussed—celestial bodies,magnetic fields, landmarks—they’ve got a lot of sensory cues at their disposal.But how do they use them?For example:do birds use one navigational cue at a time…Like being guided by stars when the sky is clear and using magnetic fields when it’s cloudy?Or,do they use all these tools simultaneously—calibrating their location from multiple cues at the same time?Does the answer depend on the particular species?This is a really rich subject for research…In fact,let’s talk about how you might go about designing some experiments to answer these questions.Keeping in mind,as I said,that your personal experiences won’t be of much use as you try to come up with hypotheses to test.题目1.What does the professor mainly discuss in the lecture?[Click on2answers.]A.Some ways birds benefit by having homing abilitiesB.Several ways that birds improve their homing abilitiesC.Some navigational tools that birds use in migration and homingD.Several research studies that measure migration and homing abilities in birds2.According to the professor,what are three ways in which homing behavior is different from migration behavior in birds?[Click on3answers.]A.Homing is not a seasonal activity.B.Homing does not always involve long distances.C.Homing behavior is learned rather than instinctive.D.Homing abilities allow birds to deal with unexpected situations.E.Homing requires the use of different navigational tools than does migration.3.According to the professor,birds often take a different route when they leave the nest to hunt for food than they do when they return to the nest.What is one reason for this behavior?A.Birds use the return flight to teach their young homing skills.B.Birds want to complete the return trip as quickly as possible.C.By taking different routes,birds have access to more food sources.D.By taking different routes,birds avoid predators that may try to follow them.4.Why does the professor mention a study with gannets?A.To identify a bird species that does not migrate long distancesB.To explain that some birds fly in spiral patterns until they locate food sourcesC.To illustrate differences in behavior between coastal and mountain bird speciesD.To demonstrate that some birds use distinctive features of the landscape as a navigation tool5.What does the professor imply about the design of research experiments that the students might conduct on bird navigation?A.Well-designed research studies help to explain human as well as bird navigational abilities.B.Past research studies were mistakenly designed to study only one navigational skill at a time.C.Students need to be careful to avoid designing experiments that are based on faulty assumptions.D.Students should try to design experiments that challenge traditional theories about birds’navigational abilities.6.Why does the student say this?FEMALE STUDENT:I think so.I mean we talked about using the Sun and the stars as navigational guides—and that would certainly be helpful for homing.And so would that ability to sense Earth’s magnetic poles—the one in the studies you described about the,uh,internal magnetic compass birds have.Yeah,it should be the same.A.To establish a connection between two scientific studiesB.To point out that the professor mentioned these details in a previous classC.To indicate she is confident that her initial response was correctD.To show that she agrees with the professor’s interpretation of a theory答案AC ABD B D C C译文旁白：在生物课上听一节课的部分内容。
托福听力tpo62 lecture1、2、3 原文+题目+答案+译文
托福听力tpo62 lecture1、2、3 原文+题目+答案+译文Lecture1 (1)原文 (1)题目 (3)答案 (5)译文 (6)Lecture2 (7)原文 (7)题目 (10)答案 (12)译文 (12)Lecture3 (14)原文 (14)题目 (16)答案 (18)译文 (18)Lecture1原文Listen to part of a lecture in an architectural history class.Professor: Now we’ve talked about how social concerns inform the designs of some architects in the United States in the 19th century. And it holds true not only for building architects but also for landscape architects. The way we design our landscapes is hugely important to, for how we live, easily as important as the buildings we live in. And these social concerns were especially apparent in the work of a huge figure in the history of landscape architecture: Frederick Law Olmsted. Olmsted is particularly associated with the building of public parks in the mid-1800s. At that time, with industrialization, the United States was moving from a rural, agricultural way of life to an urban one. Many people were moving from farms to cities, and cities themselves were growing fast. And that was creating concern and anxiety about people losing touch with nature.Now, based on your reading, how did this situation relate to Olmsted? Ken.Male Student: Well, he saw that as cities grew to accommodate the larger populations, a lot of open space would be used up for buildings and infrastructure. I guess he thought that eventually there might not be any open space left, green space.Professor: And others shared this concern as well, people with some power.Male Student: Right. So in New York City, they decided to build this huge park, Central Park. And they hired him to design it.Professor: Right. Olmsted together with Calbert Vaux. And he, what Olmsted wanted to do through this park and others was to preserve people’s connections with the natural world. Central Park is his best-known project and it really launched his career. There were so many details that made this such a model of success that…yeah, Julia. Female Student: It seems like he integrated the park into the city really well, especially by putting streets across the park so that you can still get from one side of the city to the other.Professor: And those streets don’t disrupt the unity of the park very much. But why not? What feature, what modification did he make?Female Student: Well, they weren’t any narrower than any regular city streets. Professor: No, not narrower.Female Student: Oh, lower. He put them at a lower level than the rest of the park and used short tunnels.Professor: Yes, exactly. The streets were designed to be as unobtrusive as possible, not interrupting the flow of people walking in the park, not interfering with the natural setting, while still functioning as streets.Making tunnels was the best way to achieve this balance in many locations within the park, and then pass for pedestrians went above the street throughout the park.What’s so special about it to me is Olmsted did such a good job of using the space by emphasizing the natural elements of the park. So with ground areas that were low, he made them even lower and turned them into ponds and meadows, then he emphasized some high, rocky areas. He used…he planted small forests close to grassy meadows. By doing this, he emphasized contrast in contour and texture, but he made it all work as a whole. He also made the northern half of the park more of the nature preserve while the southern part was more for people and recreation.So Central Park was a huge success and it led to more work for him. He designed dozens of urban parks throughout the country. So that’s probably his greatest legacy to architecture as a profession, but not his only legacy.He also designed landscapes for public buildings, campuses, even entire towns. In that area, urban planning, he showed the same concern for preserving open spaces that he had shown with Central Park. For example, his design of a town of Riverside, Illinois. He planned it so it would have the conveniences of city living, but it also had open space for recreation for nature. He lowered the streets slightly so they wouldn’t block natural views, like views of the Des Plaines River, which flows through Riverside. He really wanted to preserve the shores of the river so he didn’t put houses there. Instead, he turned the river front area into a park. And about a quarter of Riverside is parks.What’s also remarkable is that Riverside, well, even today, the streets and other parts of Olmsted’s plans are almost completely intact. It’s really an oasis in the city that’s grown around it, the city of Chicago, since that time. Goes to show you how valuable good design really is.题目1.What is the lecture mainly about?A. The reasons why Olmsted was selected to design Central ParkB. The impact that Olmsted's designs had on the growth of citiesC. Ways that Olmsted's design for Central Park influenced the design of Riverside, IllinoisD. Olmsted's design goals as revealed in two of his projects2.What does the professor imply about the increase in the population of urban areas in the middle of the nineteenth century?A. It caused difficulty in the design and creation of city parks.B. It was one of the reasons that Central Park was created.C. It forced Olmsted to build more roads in Central Park than he had originally planned.D. Olmsted viewed the increase in population as a positive trend.3.What is one of the features of Olmsted's design of Central Park that the professor particularly admires?A. The use of trees as boundaries between recreational and non-recreational areasB. The emphasis of naturally occurring contrastsC. The quality of the materials used for streets and buildingsD. The wide variety of styles used for its tunnels4.What design feature did Olmsted incorporate into both Central Park and the town of Riverside, Illinois?A. Forest areas that were left undisturbedB. Streets at lower levels than other ground areasC. The removal of large rocks that obstructed viewsD. The expansion of naturally occurring ponds5.What does the professor say about the town of Riverside, Illinois today?A. It has stayed true to Olmsted's original design.B. It is regarded as Olmsted's most successful project.C. It has even more parkland than Olmsted had created.D. It has nicer parks than the city of Chicago does.6.What can be inferred about the woman when she says this:Professor: And those streets don’t disrupt the unity of the park very much. But why not? What feature, what modification did he make?Female Student: Well, they weren’t any narrower than any regular city streets. Professor: No, not narrower.A. She believes there is more than one correct answer to the professor's question.B. She realizes she is repeating a point the professor made earlier.C. She recognizes that she is not giving a correct answer.D. She thinks the answer to the professor's question is obvious.答案D B B B A C译文请听建筑史课上的部分内容。
托福听力tpo69 lecture1、2、3 原文+题目+答案+译文
托福听力tpo69 lecture1、2、3 原文+题目+答案+译文Lecture1 (2)原文 (2)题目 (5)答案 (8)译文 (8)Lecture2 (10)原文 (10)题目 (14)答案 (17)译文 (17)Lecture3 (20)原文 (20)题目 (23)答案 (26)译文 (26)Lecture1原文So, we've talked about the plates that form the earth crust and their movements and how in some places they're separating. Now, when this happens in the ocean along a middle ocean ridge, some important things can happen, in particular you can get a hydrothermal vent. This is a lot like a geyser except it’s on the ocean floor.A geyser of course is a kind of eruption from underground hot spring. Water that’s been heated up in Earth’s interior, when under pressure, can erupt, sending that water and steam, shooting upwards through crack in the earth. A hydrothermal vent is essentially this same thing, but the water is emitted out of cracks or, or fractures in the ocean floor. If Forms that don't depend on energy from the sun, but depend on chemical energy.But, the vents are also enormous significance for us. From a purely geological perspective, because the chemistry of the oceans is affected by them. To see how, let’s look at the process a little more closely. They typically occur in fields, so you might have an area with a dozen of them, but you need two things to get one of these fields, first, you got haveheat. And you’ve got have fissures in the ocean floor. So, in a vent field, you've got cracks in the ocean floor. And cold water at the bottom of the ocean, we are talking, maybe two degrees Celsius, goes down into them, as it goes underground, it heats up, because in these fields, there are magma chambers, only a few kilometers below the ocean floor.This hot molten rock heats the solid rock above it to as high as five hundred degrees Celsius. And this heated solid rock, then heats the ocean water that flows over it. Now remember, the high pressure of the deep sea, allows water to stay liquid at such a high temperature, so it can reach temperatures of, three or four hundred degrees Celsius.As the water heated, it rises up through other cracks and it shoots up back into the ocean, much like with geyser on land. Now, the important part, is what the water is carrying with it, as it emerges. The heated water draws minerals from solid rock. So, you get dissolved metals in the water, like iron and copper. When the water shoots up and re-enters the cold ocean, it quickly cools and these minerals precipitate out. They’re released and they are deposited into the ocean water, which affects its composition. And it also creates quite a site, these vents have a plume that looks like a smoke, likes smoke that’s coming up out of the vent in the earth.Remember some of the water coming out of the vents is over threehundred degree Celsius. When it’s this hot, it dissolves sulfur, iron and other metals in the rock and it interacts with. when these minerals precipitate out, the water forms of black plume, so these vents are called black smokers. It's the sulfur and metals precipitating out of the water that that's what causes black color.But there are also white smokers, these emit what looks like a white smoke. That's because their water is relatively cool, above one hundred to three hundred degrees. Still pretty warm, but, not warm enough to dissolve sulfur or iron. Instead, they draw off different minerals from rocks. Things like silica and they give off different color, whitish color, when those minerals precipitate out.But in both black and white smokers as the waters emitted in the plume, the mineral that precipitate out, eventually build up around the vent, forming large, tower, like structures or minerals, build up layer upon layer, we call these chimneys, just like a chimney on a house. Different minerals will tend to build up at different places on the chimneys. But, some of the minerals like silica, a form kind of cement, and they hold the whole structure together. So, they can grow quite large and quite quickly. If you can believe it there was one chimney that reached forty-seven meters, that’s like fourteen story It collapsed, but it’s actually now rebuilding.题目1.What does the professor mainly discuss?A. The process by which molten rock can enter the oceanB. The formation of hydrothermal ventsC. The differences between geysers and hydrothermal ventsD. The mineral composition of hydrothermal vent chimneys2.According to the professor, what is the main difference between geysers and hydrothermal vents?A. Where they occurB. What causes themC. The size of their plumesD. The temperature of the water they emit3.What aspect of hydrothermal vents is of most significance to the professor?A. Their role in supporting unusual life formsB. Their role in affecting the chemical composition of the oceansC. Their role in affecting the movement of ocean platesD. Their role in affecting the temperature of ocean water4.What conditions are needed for hydrothermal vents to form?[Click on2 answers.]A. Heated rock beneath the ocean floorB. Rocks on the ocean floor with high mineral contentC. Cracks in the ocean floorD. Strong ocean currents5.What are two differences between black smokers and whitesmokers?[Click on 2 answers.]A. Black smokers emit water at a higher temperature.B. Black smokers are more common than white smokers are.C. Black smokers are found in deeper ocean water.D. Black smokers release different types of minerals than white smokers release.6.What does the professor say about the chimney structures that grow around hydrothermal vents？A. They last only a few years.B. They are formed by a single mineral.C. They can grow very tall.D. Their growth rate depends on the temperature of the water emitted from the vent.答案B A B AC AD C译文我们之前讨论了构成地壳的板块及其运动，以及在某些地方它们如何分离。
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1
Community service【社区服务】is an important component of education here at our university.
在我们大学这里，社区服务是教育的一个重要组成部分。
We encourage all students to volunteer for at least one community activity before they graduate.
我们鼓励所有的学生在他们毕业前至少志愿参加一次社区活动。
A new community program called "One On One"【一对一】helps elementary students who've fallen behind.
一个新的社区计划，叫做“一对一”，帮助落后的小学生
You education majors might be especially interested in it because it offers the opportunity to do some teaching—that is, tutoring in math and English.
你们教育专业的可能对此很感兴趣，因为它提供了教学的机会，也就是说，辅导数学和英语
You'd have to volunteer two hours a week for one semester. You can choose to help a child with math, English, or both.
你们必须在一学期内每周志愿服务两个小时。
你可以选择帮助一个孩子的数学、英语或两个都帮。
Half-hour lessons are fine, so you could do a half hour of each subject two days a week.
半个小时的课程就好，所以你可以每项做半个小时, 一周做两天。
Professor Dodge will act as a mentor to the tutors【家教】---he'll be available to help you with lesson plans or to offer suggestions for activities.
教授会担任家教们的辅导者，他将能够帮你做授课计划或者提供活动的建议
He has office hours every Tuesday and Thursday afternoon.
他每周二、四的下午有工作时间。
You can sign up for the program with him and begin the tutoring next week.
你可以在他那儿报名参加计划，并且下周开始家教。
I'm sure you'll enjoy this community service and you'll gain valuable experience at the same time.
我相信你将会享受这个社区服务，同时你将获得有价值的经验
It looks good on your resume【简历】,too, showing that you've had experience with children and that you care about your community.
这个也会在你的履历上看起来很好，显示你有教育孩子方面的经验，同时表明你很关心你的社区。
If you'd like to sign up, or if you have any questions, stop by Professor Dodge's office this week.
如果你想报名参加，或者你有任何问题，这周拜访一下Dodge教授的办公室。
2
I hope you've all finished reading the assigned(指定)chapter on insurance （保险）so that you're prepared for our discussion today.
我希望你们已经完成了关于保险的指定章节的阅读，这样你就为我们今天的讨论做好了准备。
But, before we start, I'd like to mention（提到）a few things your text doesn't go into.
但是，在我们开始之前，我想要提几件你们课本上没有探究的事情。
It's interesting to note that insurance has existed in some form for a very long time.
值得注意的是，保险已经以某种形式存在了很长一段时间了。
The earliest insurancepolicies（政策）were what we are called bottomry （船舶抵押契约）（use boats as mortgage契约）contracts（合同）.
最早的保险政策被我们称作压船借款的合同。
They provided shipping protection for merchants（商人）as far back as 3000 B.C.
他们早在公元3000年前就为海运商人提供了保护。
In general, the contracts were often no more than verbal agreements.
一般来说，这些合同也只是口头协议。
They granted（拨款）loans to merchants with the understanding that if a particular（特别的）shipment（装运，载运量）of goods was lost at sea, the loan didn't have to be repaid.
他们借款给商人，并带有这样的解释:如果一船特定的货物损失在海上，那么贷款不必偿还。
Interest on the loans varied according to how risky（冒着…的风险）it was to transport the goods.
贷款利息的变化，取决于运送货物的风险程度。
During periods of heavypiracy（海上抢劫）at sea, for example, the amount of interest and the cost of the policy went up considerably（相当大的，该注意的）.
当海盗泛滥的时期，举例来说，贷款利息的数量和担保的代价也会变得相当大。
So, you can see how insurance helped encourage international trade.
所以你可以看到保险是如何帮助和激励国际贸易的。
Even the most cautious（小心，谨慎）merchants became willing to risk shipping their goods over long distances（路程）, not to mention in hazardous（冒险）weather conditions when they had this kind of protection available.
当他们能得到这种保护时，尽管是谨慎的商人也变得愿意冒险去长距离运送他们的货物，更不用说在天气恶劣的情况下了。
Generally speaking, the basic form of an insurance policy has been pretty
much the same since the Middle Ages.
一般而言，保险的形式从中世纪以来基本是一致的。
There are four points that were salient（显著的，突出的）then and remain （残留）paramount（最高，至上）in all policies today.
那是有四点是突出的，并且至今在所有的保险中依然是重要的。
These were outlined（概述）in chapter six and will serve as the basis for the rest of today's discussion.
这些被概述在第六章，并且作为今天剩余讨论的基础。
Can anyone tell me what one of those points might be?
有人可以告诉我这几点的其中之一是什么吗？。