Polar bears are one of the most popular animals for people. Polar bears are different from every other bear in the world. This is because polar bears have white fur. However, there are many facts abou 题目和参考答案——青夏教育精英家教网—

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Polar bears are one of the most popular animals for people. Polar bears are different from every other bear in the world. This is because polar bears have white fur. However, there are many facts about polar bears that people might not be aware of .

The skin of polar bears is black, which according to thinkquest.org allows them to absorb more heat from the sun. Polar bear fur is transparent , because it is made up of hollow guard hairs. Loc.gov explains that the reason polar bears display white fur is that when the sun hits the fur ,the hollow spaces in the hair scatter the light. Since none of the light is absorbed, the light reflected back appears white to human eyes.

Polar bears’ conservation status is considered close to extinction. Global warming is considered the main cause of the decline in polar population. Polar bears use ice floats to hunt for their food. However, these ice floats are melting so polar bears are starting to drown in the search for food ,and the food is becoming more difficult to get. Contrary to popular belief, polar bears do not eat penguins ,because polar bears are not found in the Antarctic region of the world. Polar bears are only found around the Arctic Circle. Polar bears do not drink water. They get all the water they need from the prey they eat.

FES. Gov specifies that polar bears are considered the largest land carnivores(食肉动物) in the world. The polar bear weight ranges between 700--1,500 pounds. Since the polar bear habitat is melting away, their main evolutionary advantages are fading. Polar bears are not able to use their camouflage(伪装) to find prey in habitats not covered with snow. Polar bears do not hibernate(冬眠). However, when the weather gets uncomfortable, or mothers give birth, polar bears will dig themselves a hidden home.

What can we do to help save the polar bears? We can donate to organizations like the World Wildlife Fund, reduce our carbon footprint, and send letters to politicians explaining to them that we need to set up more preserves to help save the polar bear habitat.

1.What do we know about the fur of the polar bears?

A. It absorbs more heat from the sun.

B. It is black and hollow.

C. Light can pass through it.

D. It is white actually.

2.What does “main evolutionary advantages” in Paragraph 4 refer to？

A. Hibernation habit B. The function of their fur

C. Eating meat D. Their weight

3.What do we know from the passage?

A. Polar bears face danger due to the melting of ice floats.

B. The biggest polar bears weigh about 1,000 pounds.

C. Polar bears never hibernate and do not need water.

D. Polar bears are the largest carnivores in the world.

4.Which of the following ways is NOT the measure used to protect polar bears according to the passage?

A. Donating to wildlife conservation organizations.

B. Trying our best to reduce greenhouse gases.

C. Writing letters to make people protect polar bears.

D. Setting up more polar bear conservation organizations.

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Hollywood’s theory that machines with evil(邪恶) minds will drive armies of killer robots is just silly. The real problem relates to the possibility that artificial intelligence(AI) may become extremely good at achieving something other than what we really want. In 1960 a well-known mathematician Norbert Wiener, who founded the field of cybernetics（控制论）, put it this way: “If we use, to achieve our purposes, a mechanical agency with whose operation we cannot effectively interfere(干预), we had better be quite sure that the purpose put into the machine is the purpose which we really desire.”

A machine with a specific purpose has another quality, one that we usually associate with living things: a wish to preserve its own existence. For the machine, this quality is not in-born, nor is it something introduced by humans; it is a logical consequence of the simple fact that the machine cannot achieve its original purpose if it is dead. So if we send out a robot with the single instruction of fetching coffee, it will have a strong desire to secure success by disabling its own off switch or even killing anyone who might interfere with its task. If we are not careful, then, we could face a kind of global chess match against very determined, super intelligent machines whose objectives conflict with our own, with the real world as the chessboard.

The possibility of entering into and losing such a match should concentrate the minds of computer scientists. Some researchers argue that we can seal the machines inside a kind of firewall, using them to answer difficult questions but never allowing them to affect the real world. Unfortunately, that plan seems unlikely to work: we have yet to invent a firewall that is secure against ordinary humans, let alone super intelligent machines.

Solving the safety problem well enough to move forward in AI seems to be possible but not easy. There are probably decades in which to plan for the arrival of super intelligent machines. But the problem should not be dismissed out of hand, as it has been by some AI researchers. Some argue that humans and machines can coexist as long as they work in teams—yet that is not possible unless machines share the goals of humans. Others say we can just “switch them off” as if super intelligent machines are too stupid to think of that possibility. Still others think that super intelligent AI will never happen. On September 11, 1933, famous physicist Ernest Rutherford stated, with confidence, “Anyone who expects a source of power in the transformation of these atoms is talking moonshine.” However, on September 12, 1933, physicist Leo Szilard invented the neutron-induced(中子诱导) nuclear chain reaction.

1.Paragraph 1 mainly tells us that artificial intelligence may ________.

A. run out of human control

B. satisfy human’s real desires

C. command armies of killer robots

D. work faster than a mathematician

2.Machines with specific purposes are associated with living things partly because they might be able to ________.

A. prevent themselves from being destroyed

B achieve their original goals independently

C. do anything successfully with given orders

D. beat humans in international chess matches

3.According to some researchers, we can use firewalls to ________.

A. help super intelligent machines work better

B. be secure against evil human beings

C. keep machines from being harmed

D. avoid robots’ affecting the world

4.What does the author think of the safety problem of super intelligent machines?

A. It will disappear with the development of AI.

B. It will get worse with human interference.

C. It will be solved but with difficulty.

D. It will stay for a decade.

Many Chinese brands, __________their reputations over centuries,are facing new challenges from the modern market.

A.having developed B.being developed C. developed D. developing

Have you ever tasted or perhaps heard of sugar painting? As fewer people choose to make this kind of painting, the traditional Chinese folk craft might have become a 1.(distance)memory in some ways.2., a 38-year old craftsman, Li Jianzhong, is committed to3.(keep)the art of sugar painting alive.

Li worked as a miner for more than ten years. After 4.mine closed down, Li turned to housing decoration, until he 5.(force) to give that up due to a finger injury. Earlier this year, he discovered sugar painting, something he really had an interest in and a strong desire to learn.

Since there was no sugar painting craftsman in his village, he studied by 6.(he) through large quantities of videos and information on the internet. Li loved painting when he was young, and he found it easy7.(learn) the skill in sugar painting. He soon mastered the skill and could make a 8.(vary) of sugar paintings. A sugar painting is made with melted brown or white sugar. Craftsmen 9.(normal) paint animals and flowers on a stone board with the syrup(糖浆). When the sugar cools down, 10.appears is a piece of sugar art.

假设你是李华,你校外教David对中国长城很感兴趣。本周六你们学校邀请清华大学的王教授到校进行有关长城的讲座。请你给David发一封电子邮件,邀请他来参加讲座并向他介绍讲座的有关事宜。

1.讲座内容:长城修建原因及其建筑特点；

2.讲座的时间:5月7日(星期六)上午8:00---11:00；

3.讲座地点:3号教学楼一楼102室；

4.讲座后还将有提问环节。

注意:

1.词数100 左右；

2.可以适当增加细节,以使行文连贯；

3.开头和结尾已为你写好,不计入总词数。

参考词汇: 清华大学Tsinghua University

Dear David,

____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

____________________________________________________________________________________________________________________________________

Yours,

Li Hua

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。

Dear Mommy.

Happy Mother's Day! This is a special holiday because that it is a day for you to feel the appreciation for all you have done for Amy and 1. I am most thankful for all the sacrifices you had made in order for us live the most comfortable lives possible. You put yourself in difficulty situations so that we have food to eat, clean clothes to wear and a warm home to sleep in. Thank you for your endless love and hard works. Your efforts are never taking for granted. I really couldn’t ask for the better mom. Through you, I am able to understand which true love is: loving someone unconditional for what they were, are and will be.

Love,

Anna

When summer arrives, it's not uncommon to get a strong desire for sand and water. But those who can only make day-long trips may find it hard to achieve. Don't worry! Plenty of opportunities for kicking back in the sand exist here in Ohio, although it's far away from the oceans.

East Harbor State Park Beach

1169 N. Buck Rd., Lakeside-Marblehead

Those looking for a bit of extra space between their blankets and their neighbors' will like this beach. At 1,500 feet long, the sandy strip has a significant amount of real estate(房产）for sunning or relaxing in the shade. Amenities(设施）include a bathhouse, vending machines, grills and picnic tables.

Nickel Plate Beach

Corner of Tiffin Avenue and Nickel Plate Drive, Huron

Anyone who spends a day at the beach knows that swimming and doing sports on the beach give you a good appetite. Luckily, Nickel Plate Beach offers a variety of dining options nearby, including beachside pizza delivery. Amenities include a sheltered picnic area, charcoal grills, playground equipment and beach volleyball courts.

Main Street Beach

Main Street, Vermilion

No beach umbrella or chairs? No problem. This beach offers hourly rents of chairs, umbrellas, tables, shade tents and wheelchairs. And with downtown Vermilion only a block away，shops and restaurants are nicely within reach. Amenities include an observation deck and some benches. No lifeguards are on duty.

Kelleys Island State Park Beach

920 Division St. Kelleys Island

With its gradual water depth, this beach is perfect for young children. The park's campground also includes a playground and a store with snacks and ice cream. Other amenities include a picnic shelter and hiking trails.

1.What do the beaches have in common?

A. They are all at the seaside.

B. They are all close to downtown areas.

C. There are lifeguards on duty on all the beaches.

D. They serve the needs of people who cannot travel long distance.

2.Which beach is the best choice for people who don’t like to be crowded around?

A. East Harbor State Park Beach.

B. Nickel Plate Beach.

C. Main Street Beach.

D. Kelleys island State Park Beach.

3.Who will be more likely attracted by Nickel Plate Beach?

A. Hiking lovers who are going on a diet.

B. Athletic men who get hungry easily.

C. A family with two children under 10.

D. An aged couple with no shade tents.

4.Which of the following is one of the attractions of Kelleys Island State Park Beach? /

A. Children can swim in the shallow water.

B. People can rent whatever they need there.

C. Parents can leave their children with lifeguards.

D. People can do shopping and enjoy the sunshine at the same time.

As you move around your home, take a good look at the things you have. It is likely that your living room will have a television set and a video, and your kitchen a washing machine and a microwave oven. Your bedroom drawers will be filled with almost three times as many clothes as you need. You almost certainly own a car and possibly a home computer, holiday abroad at least once a year and eat out at least once a week.

Now, perhaps, more than ever before, people are wondering what life is all about, and what it is for. Seeking material success is beginning to trouble large numbers of people around the world. They feel that the long hours work culture to make more money is eating up their lives, leaving them very little time or energy for family or pastimes. Many are turning to other ways of living and downshifting is one of them. Six percent of workers in Britain took the decision to downshift last year.

One couple who downshifted is Daniel and Liz. They used to work in central London. He was a newspaper reporter and she used to work for an international bank. They would go to work by train every day from their large house in the suburbs, leaving their two children with a nanny. Most evenings Daniel wouldn’t get home until eight or nine o’clock and nearly twice a month he would have to fly to New York for meetings. They both earned a large amount of money but began to feel that life was passing them by.

Nowadays, they run a farm in the mountains of Wales. “I always wanted to have a farm then,” says Daniel, “and we took almost a year to make the decision to downshift. It’s taken some getting used to, but it’s been worth it. We have to think twice now about spending money on car repairs and we no longer have any holidays. However, I think it’s made us stronger as a family, and the children are a lot happier.

Liz, however, is not quite sure. “I used to enjoy my job, even though it was hard work and long hours. I’m not really a country girl, but I suppose I’m gradually getting used to looking after the animals. One thing I do like, though, is being able to see more of my children. My advice for other people wanting to do the same is not to think about it too much or you might not do it at all.”

1.The passage tells us that .

A. people seldom work long hours to make money

B. people hardly buy more things than necessary

C. people are sure everything they own is in the right place

D. people realize there is more to life than just making money

2.Daniel and Liz both agree that the move to the farm ____.

A. was easy to organize B. has improved family life

C. was extremely expensive D. has been a total success

3.What does the author mean by saying “the long hours work culture to make more money is eating up their lives” in the second paragraph?

A. People work long hours to earn their living.

B. To make more money through hard work is the aim of people’s life.

C. Long hours of hard work occupy too much of people’s life.

D. People spent too much time and money eating meals.

Over 2,200 years ago, Chengdu was threatened by frequent floods. Li Bing, together with his son, decided to construct an irrigation system on the Minjiang River1. (prevent) flooding. 2.having a long study and a lot of hard work by the local people, the great Dujiangyan Irrigation System was completed. Since then, the Chengdu Plain 3. (be) free of flooding and the people have been living peacefully and wealthily.

It is the4. (old) and only surviving no-dam irrigation system in the world. It is also 5. wonder in the development of Chinese science. The project consists of three important parts，namely Yuzui, Feishayan and Baopingkou, which were 6.(science) designed to control the water flow of the rivers throughout the year.

There is a glorious bridge called the Anlan Cable Bridge crossing the Minjiang River above Yuzui, 7. you can clearly see the entire system. The great 8. (construct) originally started before the Song Dynasty. At that time, the body of the bridge was constructed with wooden blocks and the handrails(扶手)were made of bamboo. Recently the wood and bamboo have been replaced with steel and concrete to guarantee the security of 9.(visit) from home and abroad. Seen from afar, the bridge looks like a rainbow 10.(hang) over the river.

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