Hummingbirds(蜂鸟) are one of nature’s most energetic fliers and the only birds to hover(盘旋) in the air by relying on their strength alone.
Now scientists have found that it is the ratio(比值) of the bird’s wing length to its width that makes them so efficient. The discovery is helping experts compete with 42 million years of natural selection to build helicopters that are increasingly efficient.
David Lentink, an assistant professor at Stanford University in California, tested wings from 12 different species of hummingbirds, which he sourced from museums. He placed them on a machine used to test the aerodynamics(气力学) of the helicopter blades(桨叶). Professor Lentink’s team used the same machine to test the blades from an advanced micro-helicopter used by the UK’s army. They found that the micro-helicopter’s blades are as efficient at hovering as the average hummingbirds.
But while the micro-helicopter’s blades kept pace with the average hummingbird wings, they could not keep up with the most efficient hummingbird’s wing. The wings of Anna’s hummingbird were found to be about 27 percent more efficient than the man-made micro- helicopter’s blades.
While Professor Lentink wasn’t surprised at nature’s superiority, he said that helicopter blades have come a long way. “The technology is at the level of an average hummingbird,” he said. “A helicopter is really the most efficient hovering device that we can build. The best hummingbirds are still better, but I think it’s amazing that we’re getting closer. It’s not easy to match their performance, but if we build better wings with better shapes, we might match hummingbirds.”
Professor Lentink said that we don’t know how hummingbirds maintain their flight in a strong wind, how they navigate(确定方向) through branches, or how they change direction so quickly. He thinks that great steps could be made by studying wing aspect ratios-the ratio of wing length to wing width. Understanding these abilities and characteristics could be a benefit for robotics and will be the focus of future experiments.
1.What did the scientists find about hummingbirds?
A. Their wings are long and wide
B. They can hover in the air for a long time
C. The ratio of their wing length to wing width is very important
D. They are the most energetic flier in nature
2.Which is the right order of Professor Lentink’s research?
①Tested wings from different species of hummingbirds
②Got resources from museums
③Analyzed the results and drew a conclusion
④Tested the blades from a micro-helicopter
A. ①②③④ B. ②①③④
C. ②④①③ D. ②①④③
3.According to Professor Lentink, what will be the focus of future experiments?
A. To know how hummingbirds can fly in a strong wind
B. To know how hummingbirds change direction so quickly
C. To develop a new kind of helicopter
D. To study the secrets of hummingbirds
科目：高中英语 来源：湖北省咸宁市五校2016-2017学年高二3月联考英语试卷 题型：信息匹配
Finding a new and fun hobby can make you a happier person.Hobbies can be a great way to relieve stress and bring more joy into your life.Specifically when you find a new hobby.Hobbies are for everyone at any age.When you get older,you should not have fewer hobbies.1.You might be looking for a new hobby,but you're not sure what.A new hobby requires finding new interests,which means experimenting to find those interests.
Try new things.To find a new hobby,it will require trying new things.New hobbies won't usually just find you. Don't put things off.You might think to yourself, "I don't like that." If you've never done it,or given it a chance,how can you know?2.
Learn new things.You're never too young or old to learn more in life.If you take the time to learn new things, you'll develop new interests.Let your curiosity run wild,and develop more knowledge over the things you don't know or are familiar with.3.Reading the same sports newspaper every day doesn't count as a new and fun hobby.
Collect things.4.Start collecting them.Maybe you have an interest in coins,or specific jewelry.Think about certain interests that pertain to（关于）what you can collect.If you're a sports fan,then collect sport cards,or jerseys. Simple hobbies aren't always a bad thing.You can collect just about anything.
5.Everyone has a creative side.Some people find different ways of expressing that side to them.It can be writing,drawing,painting,playing a music instrument,photography,dancing,or singing.These can be fun and relaxing hobbies to have that can be a positive way of expressing your emotions.
A.Interact with others.
B.Think of the things that you do like.
C.Learning is not such a bad thing.
D.Find and express the creative side in you.
E.Have an open mind and give things a chance.
F.Otherwise you'll develop more stress and gray hairs.
G.Write down a list of the leisure activities you enjoy.
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科目：高中英语 来源：河北省2016-2017学年高一下学期三调考试英语试卷 题型：完形填空
One day I was walking to the mailbox with my dad,when I saw something drop from a tree.I couldn't____what it was,so I kept my eyes on the spot as we came near.It was a baby bird,which had fallen from its nest.It had long, awkward wings and feet,and____that fought to stay open.It was____,so I sat next to it watching while my dad got the mail.I____its nest and mother,____what would happen to it.
My dad said we had to____it;there was nothing we could do.He said if the bird mother smelled any traces（踪迹）of____,she wouldn't go near the____again.
As we began to walk away,a woman____."Did it fall out of a nest?"she asked.
"Yeah."I answered.
"It____a lot.Not much we can do,"she said."Try not to think about it when you go to sleep tonight."
I walked____the mailbox the next day.The baby bird lay____in the grass.
I realize that "Try not to think about it" is the____of many people towards things which____to provide them with perfect excuses____not bothering.The woman wasn't being____;she was actually quite nice.But when everyone says "there's____I can do—just try not to think about it,"where will we finally____?When billions of people____try not to think about it when they go to bed at night,there might be millions of fallen birds lying dead and____in the grass the next morning.
1.A. say B. talk C. speak D. tell
2.A. eyes B. arms C. feathers D. claws
3.A. bored B. stupid C. lovely D. clever
4.A. turned back B. stared at C. pointed to D. looked for
5.A. suggesting B. deciding C. wondering D. finding
6.A. help B. leave C. catch D. kill
7.A. children B. humans C. animals D. insects
8.A. tree B. grass C. baby D. person
9.A. returned B. interrupted C. approached D. left
10.A. happens B. cries C. suffers D. changes
11.A. from B. beyond C. past D. into
12.A. asleep B. dead C. still D. alive
13.A. attitude B. feeling C. consideration D. understanding
14.A. fail B. prove C. refuse D. seem
15.A. from B. of C. about D. for
16.A. cruel B. kind C. silly D. friendly
17.A. something B. nothing C. everything D. anything
18.A. start out B. come from C. settle down D. end up
19.A. possibly B. simply C. particularly D. luckily
20.A. forgotten B. buried C. eaten D. remembered
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科目：高中英语 来源：广西省桂林市2017届高三下学期适应性考试英语试卷 题型：完形填空
Falling off a box car and landing on my head, I lost my sight when I was four years old. Now I am thirty-two. I can _________ remember the brightness of sunshine. It would be wonderful to see again, _________a tragedy can do strange things to people.
It _________ to me that I might not have come to love life as I do now if I hadn’t been blind. My parents and my teacher saw something _________ me , and they made me want to __________ against blindness.
The hardest _________ I had to learn was to believe in myself. If I hadn’t been able to do that, I would have ________ down and become a chair rocker for the rest of my life. When I say _________in myself I am not talking about _________ the kind of self-confidence that _________ me down an unfamiliar staircase （楼梯）alone. But I mean something bigger than that : an assurance that I am a real positive person _________ imperfections.
It took me years to obtain this ________ . It had to start with the ________ . Once a man gave me an indoor _________ . “ I can’t use this.” I said. “ Take it with you,” he ________ me , “ and roll it around.” The _________ stuck in my head. “ Roll it around !” By rolling the ball I could hear where it went. This gave me an idea how to achieve a goal I had thought _________ . At the School for the Blind I ________ a new kind of baseball called ground ball. All my life I have set a series of goals and then tried to reach them, one at a time. I had to learn my _________ . I would fail sometimes anyway but on the average I made _________ .
1.A. randomly B. abruptly C. roughly D. completely
2.A. so B. but C. thus D. and
3.A. occurred B. referred C. brought D. turned
4.A. of B. for C. to D. in
5.A. get B. fight C. find D. drop
6.A. method B. experience C. lesson D. manner
7.A. broken B. put C. settled D. lay
8.A. courage B. ambition C. belief D. power
9.A. firmly B. simply C. fairly D. slightly
10.A. stops B. helps C. finds D. gives
11.A. despite B. besides C. without D. unlike
12.A. description B. existence C. intelligence D. recognition
13.A. intelligence B. incident C. trouble D. determination
14.A. chair B. baseball C. game D. design
15.A. urged B. blamed C. greeted D. teased
16.A. goals B. words C. baseballs D. ideas
17.A. valuable B. reasonable C. impossible D. unbearable
18.A. discovered B. equipped C. formed D. invented
19.A. limitations B. Advantages C. puzzles D. personalities
20.A. sense B. progress C. mistakes D. friends[
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科目：高中英语 来源：安徽省六安市2017届高三6月适应性考试英语试卷 题型：短文改错
假定英语课上老师要求同桌之间交换修改作文，请你修改你同桌写的以下作文。文中共有10处语言错误，每句中最多有两处。每处错误涉及一个单词的增加、删除或修改。
增加：在缺词处加一个漏字符号（∧），并在其下面写出该加的词。
删除：把多余的词用斜线（\）划掉。
修改：在错的词下划一横线（ ），并在该词下面写出修改后的词。
注意：
1.每处错误及其修改均仅限一词；
2.只允许修改10处，多者（从第11处起）不计分。
Many people like eating junk foods, because they thought they are delicious. But in fact, these foods are not healthy. That we need most is a balanced diet. Eating a balanced diet mean choosing a wide variety of foods from all the food groups. A balanced diet provides different kinds of nutrition(营养) with our body. We need a balanced diet to keep healthy. Therefore, many people still have unhealthy eating habits, that will do harm to their health. I think is necessary for us to have three meals a day properly. When eat, we should eat different kinks of foods. For an example, we should eat both meat and vegetables to get different kinds of nutrition.
All in all, it’s importantly for us to keep a balanced diet.
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科目：高中英语 来源：湖南省2017届高三学业水平考试模拟卷英语试卷 题型：单句改错
下列句子中各有一处语言错误，请把错误改正，其他部分不得改动。每处错误仅涉及一个单词的增加、删除或修改。
增加：在缺词处加一个漏字符号（∧），并在右边横线上写出该加的词。
删除：把多余的词用斜线（＼）划掉，并在右边横线上写出该词，也用斜线划掉。
修改：在错误的词下划一横线，并在右边横线上写出改正后的词。
1.Go to a British school for one year was a very enjoyable experience.
__________________________________________________________________
2.By the 1920s, he had become a explorer, searching for some tombs.
__________________________________________________________________
3.I regretted to taking those weight-loss pills a few days ago.
__________________________________________________________________
4.If you eat proper and exercise regularly, you will feel great.
__________________________________________________________________
5.He says that he is a music fan and he often plays the piano.
__________________________________________________________________
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科目：高中英语 来源：甘肃省2016-2017学年高二上学期期末考试英语试卷 题型：书面表达
美国学生Jim即将作为一名交换生到中国来学习。李先生一家是他约定好的住宿家庭（homestay）。请以Jim的名义给李先生写一封信，要点如下：
选择homestay的原因：
1．体验中国文化，了解中国，了解世界；
2．喜欢中国饮食健康；
个人要求：
1．准备独立的房间；
2．允许一家一起用早餐、晚餐（周一到周五）。
注意：
1．词数100字左右；
2．文章的开头和结尾已给出，不计入总词数；
3．可以适当增加细节，以使行文连贯。
Dear Mr Li,
I am very glad to be a guest of your family. Thank you for accepting me.
____________________________________________________________________________________________
____________________________________________________________________________________________
____________________________________________________________________________________________
____________________________________________________________________________________________
____________________________________________________________________________________________
____________________________________________________________________________________________
_______________________________________________________________
Best wishes!
Yours sincerely,
Jim
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科目：高中英语 来源：山西省太原市2017届高三第三次模拟英语试卷 题型：阅读理解
Dear Parents:
I’m delighted that you are considering the British International School for your children’s education. Our school offers first class international education delivered by experienced, highly qualified and professional staff.
We aim to provide a high quality British-style education characterized by:
The arrangement of the English National Curriculum to meet the needs of international and local students and offering an insight into the local culture.
High quality teaching provided by international and local staff.
A broad personal development of students that encourages independence, confidence, tolerance, good manners and respect.
A recognition of the school-parent partnership in the successful education of the children.
An acknowledge that all students are individuals who deserve an environment to help realize their academic and other potential, thereby preparing them for their chosen continued education and career.
A safe, caring, happy and stimulating environment benefiting from high quality facilities.
Our school provides an effective framework for education through a broad, balanced, and monitored curriculum. As students advance through the school, we ensure that their needs are met through progressive teaching and learning. Although our curriculum is based upon the National Curriculum for England, it is adapted as appropriate, to ensure suitability for our diverse student body. Thus, we strive for the development of transferable skills through the years of school, as well as the acquisition of a broad body of knowledge.
Students are given opportunities to develop many skills. These include skills in language, in science, technology and mathematics, in the aesthetic(审美的) and creative fields of music, drama and art, and in physical education.
We insist that students act in a responsible manner toward all members of society. Throughout the school, students are taught to distinguish between right and wrong and show consideration for others. The qualities of honesty, kindness and good manners are always encouraged. Our friendly atmosphere provides a secure and happy environment in which children can grow and flourish as Individuals and valued members of the school family.
1.What do you think the author is?
A. A school principal
B. An exchange student.
C. An assistant professor
D. An experienced lecturer.
2.Why does the school change its curriculum when necessary?
A. To develop some good students’ skills.
B. To meet the needs of different students.
C. To offer an insight into the local culture.
D. To help students realize their potential.
3.Which of the following about the students is NOT mentioned in the passage?
A. Manners
B. Self-discipline
C. Qualities.
D. Independence.
4.What is the purpose of the passage?
A. The author thinks schools and parents play an important role in teaching.
B. The author is stressing that responsibility is the most important thing for a student.
C. The author is encouraging more parents to send their children to this school.
D. The author implies students become valued people without a friendly atmosphere.
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科目：高中英语 来源：江苏省盐城市阜宁县2016-2017学年高一下学期期中考试英语试卷 题型：阅读理解
From self-driving cars to deep sea explorers, more and more of humans’ tasks are being taken over by robots. But technology doesn’t stop there. In mid-August, reported the BBC, scientists from Cambridge University developed a robotic system that meant a robot could “build other robots, each one better than the previous(以前的) generation”.
The BBC noted that “those concerned about machines taking over the world shouldn’t worry”.
However, over 1,000 scientists and numerous artificial intelligence (AI, 人工智能) researchers－including UK astrophysicist Stephen Hawking and Apple cofounder Steve Wozniak of the US-brought the danger of fully autonomous weapons(自主武器), known as “killer robots”, to our attention earlier this summer.
“If any major military(军事的) power pushes ahead with AI weapon development, a global arms race is inevitable(不可避免的),” warned an open letter released at the International Joint Conference on Artificial Intelligence held in Buenos Aires, Argentina.
Unlike drones(无人机), which need a human hand, this kind of robot would have some decision-making abilities and the ability to act by itself. While what the BBC called these “solders that never sleep” could help reduce battlefield deaths, they might also make countries more likely to go into battle, which would lead to more deaths overall, noted the scientists. The risks, they said, could be far greater than those posed by nuclear weapons.
Scientists called for a “ban on offensive(攻击性的) autonomous weapons beyond meaningful human control”, reported The Huffington Post.
In fact, in an interview with the BBC in 2014, Hawking warned that the “development of full artificial intelligence could spell the end of the human race”.
And according to the BBC, many leading thinkers have been thinking about the AI-powered killing machine of the not-too-distant future. “Killer robots could be here within years, not decades,” as Stuart Russell, professor of computer science at UC Berkeley, US, put it.
Authorities are gradually waking up to the risk of robot wars. Last May, for the first time, the United Nations brought governments together to begin talks on so-called killer robots in a hope of stopping such weapons while there is still time.
Meanwhile, there are scientists who are less worried. They believe all technologies have potential(潜力) for being used for good and evil ends, and argue that the ban called for by the open letter could close the door to developing AI technology that could save lives. “Technology can clearly do better than human beings in many cases,” Ronald Arkin, dean at the Georgia Institute of Technology in Atlanta, US, told The Christian Science Monitor. “If we are willing to turn over some of our decision making to these machines, we may actually get better outcomes.”
1.What does Steve Wozniak think the future robot technology might produce?
A. Artificial Intelligence. B. Autonomous weapons.
C. Soldiers that never sleep. D. Killing machines.
2.The underlined word “spell” in Paragraph 7 is closest in meaning to “______”.
A. cause B. prevent
C. reach D. change
3.What does Stuart Russell mean by saying “killer robots could be here within years, not decades.”?
A. Killer robots will visit UC Berkeley, US sooner than expected.
B. Killer robots will be produced and used sooner than expected.
C. Killer robots will speed up the development of AI in the near future.
D. Killer robots will kill these scientists in the near future.
4.What is the main idea of the text?
A. More and more of humans’ tasks are being taken over by robots.
B. Robots have decision-making abilities and the ability to act by itself.
C. Scientists called for a ban on the development of robot technology.
D. All technologies have potential for being used for good and evil ends.
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