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Water is essential to the growth of crops. 必要的 There is no essential difference between them. 本質(zhì)上的 查看更多

 

題目列表(包括答案和解析)

Stepping into a pool of water is common enough, but who could ever imagine stepping into a pool of fish? In February of 1974, Bill Tapp, an Australian farmer, saw a rain of fish that covered his farm. How surprised he must have been when he heard many fish hitting against his roof!

   What caused this strange occurrence? This is a question that had long puzzled people who study fish. The answer turned out to be a combination of wind and storm.

  When it is spring in the northern part of the world, it is fall in Australia. Throughout the autumn season, terrible storms arise and rains flood the land. The strong winds sweep over Australia like huge vacuum cleaners, collecting seaweed, pieces of wood, and even schools of fish. Strong winds may carry these bits of nature for many miles before dropping them on fields, houses, and astonished people.

  Although they seem unusual, fish-falls occur quite frequently in Australia. When Bill Tapp was asked to describe the scene of fish, he remarked, “They look like millions of dead birds falling down.” His statement is not surprising. The wonders of the natural world are as common as rain. Nature, with its infinite wonders, can create waterfalls that flow upward and fish that fall out of the sky.

  56. What is this passage about?

  A. A sad story.             B. A rain of fish.

  C. Australia’s northern part.     D. The damage done by floods.

  57. Fish-falls occur in Australia_________ .

  A. quite often       B. on large farms

  C. only in winter     D. when the air is calm

  58. It is a known fact that ________.

  A. one should watch where one steps

  B. Bill Tapp is a scientist who studies farming

  C. the natural world can never create waterfalls that fall upward

  D. the seasons in the southern part are different from those in the northern part

  59. The word “infinite” is closest in meaning to _________.

  A. easy    B. difficult    C. countless    D. dangerous

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In 1982, Steven Callahan was crossing the Atlantic alone in his sailboat when it struck something and sank. He got into a life boat, but his supplies were???? . His chances of surviving were small.?????? when three fishermen found him 76 days later, he was alive —much?????? than he was when he started, but alive.

His?????? of how he survived is fascinating. His cleverness how he?????? to catch fish, how he evaporated (蒸發(fā)) sea water to ????? fresh wateris very interesting.

But the thing that ?????? my eye was how he managed to keep himself going when all hope seemed lost, and there seemed no ???? in continuing the struggle. He was starved and?????? worn-out. Giving up would have seemed the only possible choice.

When people?????? these kinds of circumstances, they do something with their minds that gives them the courage to keep going. Many people in ????? desperate circumstances?????? in or go mad. Something the survivors do with their thoughts helps them find the courage to carry on?????? difficulties.

I tell myself I can????? it,” wrote Callahan in his book. “Compared to what others have been through, I’m fortunate. I tell myself these things over and over, ???? up courage…”

I wrote that down after I read it. It?????? me as something important. And I’ve told myself the same thing when my own goals seemed?????? off or when my problems seemed too terrible. And every time I’ve said it, I have always come back to my ???? .

The truth is, our circumstances are only bad?????? to something better. But others have been through the much worse, that is, in comparison with what others have been through, you’re fortunate. Tell this to yourself over and over again, and it will help you??????? through the rough situations with a little more courage.

1.Afull????????????? Brich????????????? Cfew????????????? Denough

2.AAnd????????????? BYet????????????? CStill????????????? DThus

3.Athinner????????????? Bstronger????????????? Cworse????????????? Dhealthier

4.Aattitude????????????? Bassumption????????????? Cinstruction????????????? Daccount

5.Aassisted????????????? Btended????????????? Cmanaged????????????? Dintended

6.Amake????????????? Babsorb????????????? Cselect????????????? Dreplace

7.Aattacked????????????? Bcaught????????????? Cfroze????????????? Dcheated

8.Aoperation????????????? Btaste????????????? Cmessage????????????? Dpoint

9.Afirmly????????????? Bcompletely????????????? Chardly????????????? Dgenerally

10.Adeal????????????? Bdefend????????????? Csurvive????????????? Dobserve

11.Asimilarly????????????? Bdifferently????????????? Cgradually????????????? Dcommonly

12.Apull????????????? Btake????????????? Cbreak????????????? Dgive

13.Afor the lack of????????????? Bin the face of????????????? Cin exchange for????????????? Das a result of

14.Ahandle????????????? Bcarry????????????? Cfollow????????????? Dinspect

15.Arolling????????????? Busing????????????? Cbuilding????????????? Dmaking

16.Adefeated????????????? Brecommended????????????? Cintroduced????????????? Dstruck

17.Afar????????????? Blong????????????? Cever????????????? Deven

18.Afeelings????????????? Bsenses????????????? Cideas????????????? Dinfluences

19.Arelated????????????? Bmeasured????????????? Ccontributed????????????? Dcompared

20.Asee????????????? Bcut????????????? Cget????????????? Dthink

 

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 Of all the things we eat and drink, water is the most important. Not all people realize this, but it is quite true. The human body can live without food for a long time, but two or three days without water usually result in death.

Many people do not understand how much water the human body needs, but many people do not drink enough, especially in the hot weather. Most people drink when they are thirsty but often need more water after exercises.

65 to 70 percent of the human body is water. Water is important in several different ways. Most people need five to seven liters(升) of water every day, but we needn’t drink this amount(量) because a lot comes from the food we have. If we don’t have enough water, however, we will feel tired and many become ill. Do you know what the best drink is? Yes, you are right. Cool water!

1.When do we need more water?________

A.In cold weather or after exercises.

B.In hot weather or after exercises.

C.Before breakfast, lunch and supper.

D.When we feel tired or become ill.

2.How much water are there in the human body?_________

A.About three fourths of the human body is water.

B.Nearly a half of the human body is water.

C.Less than a half of the human body is water.

D.Almost one fourth of the human body is water.

3.Must most people drink five liters(升)of water every day?_______

A.Yes, because water is the most important

B.No, because what we eat contains(包含)water

C.Yes, because we can’t live without water

D.No, because we are not thirsty

4.Which of the following is not right?_________

A.Cool water is the best drink.

B.Few people understand how much water the human body needs.

C.All the people don’t realize water is the most important.

D.When we feel tired or become ill, we never need any water.

 

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Do you know Australia? Australia is the largest island in the world. It is a little smaller than China. It is in the south of the earth. Australia is big, but its population is not large. The population of Australia is nearly as large as that of Shanghai.

The government has made enough laws to fight pollution. The cities in Australia have got little air or water pollution. The sky is blue and the water is clean. You can clearly see fish swimming in the rivers. Plants grow very well.

Last month we visited Perth, the biggest city in Western Australia, and went to a wild flowers’ exhibition. There we saw a large number of wild flowers we had never seen before. We had a wonderful time. Perth is famous for its beautiful wild flowers. In spring every year Perth has the wild flowers’ exhibition. After visiting Perth, we spent the day in the countryside. We sat down and had a rest near a path at the foot of a hill. It was quiet and we enjoyed ourselves. Suddenly we heard bells ringing at the top of the hill. What we saw made us pick up all our things and run back to the car as quickly as we could. There were about three hundred sheep coming towards us down the path.

Australia is famous for its sheep and kangaroos (袋鼠). After a short drive from any town, you will find yourself in the middle of white sheep. Sheep, sheep, everywhere are sheep.

1.Australia is _______.

A.the largest country in the world

B.a(chǎn)s large as Shanghai

C.not as large as China

D.the largest island in the north of the earth

2.The government had made _______.

A.too enough laws to fight pollution

B.so many laws that it can fight pollution

C.enough laws that it can hardly fight pollution

D.enough laws because the pollution is very serious

3.Which of the following is NOT true?

A.Perth is famous for its beautiful wild flowers.

B.Perth is bigger than any other city in Western Australia.

C.Perth lies in the west of Australia.

D.No other city is larger than Perth in Australia.

4.In Perth you may visit a wild flowers’ show in _______.

A.October          B.January           C.May              D.July

5.Which of the following is true?

A.Australia is famous for its sheep, kangaroos and wild flowers.

B.We ran back to the car because we were in the middle of white sheep.

C.Three hundred sheep came towards us because they saw us.

D.If you go to the countryside in Australia, you will see a large number of white sheep.

 

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What will power your house in the future?Nuclear,wind,or solar power?According to scientists at the Massachusetts Institute of Technology (MIT) in the US,it might be leaves — but artificial (人造的) ones.

Natural leaves are able to change sunlight and water into energy. It is known as photosynthesis (光合作用).Now researchers have found a way to imitate this seemingly simple process.

The artificial leaf developed by Daniel Nocera and his colleagues at MIT can be seen as a special silicon chip with catalysts (催化劑).Similar to natural leaves,it can split water into hydrogen and oxygen when put into a bucket of water. The hydrogen and oxygen gases are then stored in a fuel cell,which uses those two materials to produce electricity,located either on top of a house or beside the house.

Though the leaf is only about the shape of a poker card,scientists claimed that it is promising to be an inexpensive source of electricity in developing countries. “One can imagine villages in India and Africa not long from now purchasing an affordable basic power system based on this technology,” said Nocera at a conference of the American Chemical Society.

The artificial leaf is not a new idea. The first artificial leaf was invented in 1997 but was too expensive and unstable for practical use. The new leaf,by contrast,is made of cheap materials,easy to use and highly stable. In laboratory studies,Nocera showed that an artificial leaf prototype (原型) could operate continuously for at least 45 hours without a drop in activity.

The wonderful improvements come from Nocera's recent discovery of several powerful,new and inexpensive catalysts. These catalysts make the energy transformation inside the leaf more efficient with water and sunlight. Right now,the new leaf is about 10 times more efficient at carrying out photosynthesis than a natural one. Besides,the device can run in whatever water is available;that is,it doesn't need pure water. This is important for some countries that don't have access to pure water.

With the goal to “make each home its own power station” and “give energy to the poor”,scientists believe that the new technology could be widely used in developing countries,especially in India and rural China.

1.Which of the following orders correctly shows how the artificial leaf is used to produce electricity?

a.a(chǎn)rtificial leaves split water into hydrogen and oxygen

b.the hydrogen and oxygen gases are stored in a fuel cell

c.the artificial leaves are put in water

d.the fuel cell uses hydrogen and oxygen to produce electricity

A. c,a,b,d                               B.c,b,a,d  

C.b,c,a,d                 D.c,a,d,b

2.The purpose of the scientists at MIT in developing the new artificial leaf is to________.

A.build up more power stations in the world

B.provide cheaper energy for developing countries

C.offer people in developing countries access to pure water

D.gain a deeper understanding of the photosynthesis process

3.The main idea of this passage is ________.

A.a(chǎn)n introduction to the history of artificial leaves

B.a(chǎn) mixture of water power and solar energy

C.giving energy to the poor

D.a(chǎn)n invention copying photosynthesis

 

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