Directions:There are 4 passages in this part. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A,B,C and D. You should decide on the best choice and mark the corresponding letter on the Answer Sheet with a single line through the centre.
Ⅰ
American scientists and engineers are developing new ways to produce energy from the sun. Many people believe solar energy will be the energy source of the future. This is because the supply of solar energy is unlimited. But some day there will be no more oil, coal or other fuels. Experts have not developed methods to produce energy from the sun at lower cost than other fuels. But American scientists are working on ways to cut the costs of solar energy production.
One recent improvement has been made in the production of solar cells for making electricity. Solar cells are usually made from the element silicon. When sunlight strikes the cell, electrons in the element become excited and can be used to produce electric power. In most solar cells the molecules are very orderly in the form of a crystal of silicon.
But American inventor Standford Oshenski has developed a way to make solar cells from silicon that is not in the form of a crystal.
These so-called non-crystaline cells cost less to produce for several reasons. They are much thinner than earlier solar cells so they use less silicon. Non-crystaline cells are formed at a lower temperature than crystaline cells, so less energy is needed to make them. And the newer kind of solar cell can be produced faster and in larger sheets than the older kind.
11.According to the passage, what will be the energy source of the future?
A.CoalB.Oil
C.Other fuelsD.Solar energy
12.The problem experts meet in producing energy is.
A.developmentB.production
C.costD.fuels
13.According to the passage, what will factories produce to make electricity?
A.The element liliconB.Solar cells
C.ElectronsD.The molecules
14.What are solar cells usually made from?
A.SiliconB.Sunlight
C.ElectronsD.Fuels
15.What is not the reason for the lower cost of non-crystaline cells?
A.They use less silicon
B.They need lower temperature
C.They can be produced faster
D.Their size is much smaller
Ⅱ
Some agriculture scientists in the United States are tesing a new way to water crops. They are testing a system that lets corn plants get water when the plants need it. The test is being done in Colorado by scientists of United States Agriculture Department. The system uses special instruments to measure the amount of water in corn plants. There instrurments send signals to a small computer that opens pipes to supply more water if needed. The measure instruments do not really measure how much water is in the plant. Insted, they examine tiny holes in the plant′s leaves. The plant takes in carbon dioxide through these holes, or pores. It also releases water vapour through them. When sunlight is shining on a plant that has enough water, the pores in the leaves are open. At night, the pores close because there is no light. They also close when the plant′s roots do not have yet enough water from the soil.
16.Colorado is a name of a .
a.labB.city
C.stateD.university
17.Which of the following has nothing to do with the growth of plants?
A.SunlightB.Moon light
C.Carbon dioxideD.Water
18.When do the pores close according to the passage?
A.In the morning B.At noon
C.In the eveningD.At night
19.Which of the following is being tested as water crops?
A.EggplantsB.Trees
C.Corn plants D.Plum plants
20.The scientists who are testing are experts in.
A.architectureB.culture
C.agricultureD.environment
Ⅲ
Captaing Spens and Mrs Spens were flying home from South Africa. They were sitting side by side in the aeroplane, for in spite of all his doubts and fears he had found it very easy to persuade her to come back with him; it had been quite unnecessary to say anything about the sack (袋) that he had brought in case she was obstinate (固执的). The truth of it was that Mrs Spens had been thinking so much about hats that she had almost forgotten how very fond of her husband she really was; but when she saw him again, it all came back to her. She realized, too, that he must be very fond of her, or he would not have gone to so much trouble and expense to bring her home; and that pleased her so much that she agreed almost at once to return to Popinsay. But neither of them was enjoying the journey, because flying made Mrs Spens feel sick, and the Captain had caught a cold.
They arrived in London, and spent a day there. Mrs Spens went shopping, and the Captain, whose cold was rather worse, began to feel seriously ill; for everything in the shops was very expensive indeed. On the following day they went aboard another aeroplane to fly to the north of Scotland, and landed on an airfield between a little town and an angry sea that broke against tall grey cliffs (悬崖). From there they drove to a nearby harbour and went aboard the small steamer that crossed every day to Popinsay. The steamer looked even smaller than usual, for the sea was extremely rough and still running high.
21.The reason why Captain Spens brought a sack with him was that.
A.he and his wife had much luggage to carry
B.he was uncertain and worried if she could be persuaded
C.Mrs Spens thought it necessary for travel
D.Mrs Spent felt sick when she was flying
22.When Mrs Spens saw her husband again, she.
A.had almost forgotten all about him
B.realized that she really loved him
C.understood his intention of persuading her to return
D.was alway so obstinate that he feared her
23.What made her agree readily to fly back was.
A.her concern about hats
B.her heartfelt regret for obstinacy
C.her husband′s effort and money
D.shopping they would have to do in London
24.Popinsay is probably a place.
A.where the couple went and fell ill
B.between a town and the sea
C.where the couple returned by air
D.off the coast of Scotland
25.We can assume that the following voyage would be.
A.tiringB.dangerous C.smoothD.long
Ⅳ
Until recently, the British system of money was not based on the decimal system. But in February 1971,Great Britain converted its currency to the decimal system. The pound is still the basic monetary unit, but it is now made up of 100 pennies or pence. In the new system, there are six coins. The coins are known by their values. They have the following values:1/2 pence or penny, 1 penny, 2 pence, 5 pence, 10 pence, and 50 pence.
In Great Britain. the word note is used to refer to paper money. THe notes you would most probably use if you visited England are the one-pound note, the five-pound note, and the ten-pound note.
It isn′t easy for a country to convert its currency from one system to another: In England the Decimal Currency Board spent £3 million to explain the new system to the people. The change to the decimal method of counting is to go much further than the money system. Great Britain will adopt the metric system for all weights and measurements. The cost will be enormous. According to one estimate, it will run to 12 billion. There must be new machinery for businesses and factories, new bottles and cans for the food and dairy industries, new traffic signs for the highwas (the speed limits and distances must be marked in kilometres rather than miles), new thermometers (water will freeze at 0 degree centigade instead of 32 degrees Fahentheit). But the changeover is inevitable. In the long run, the new system, which is uniform and simpler, will save money. And now that Great Britain has joined the Common Market it will be necessary for British exporters to use the same system as that of the other countries with which Britain has formed such close economic ties.
26.The following statements are true except that.
A.a pound consists of 100 pennies before 1971
B.a new kind of money system was adopted in Britain in 1971
C.the word note is used to refer to paper money in Britain
D.it isn′t easy for a country to convert its currency from one system to another
27.There arenotes used most probably in England.
A.two kinds of B.three kinds of
C.six kinds ofD.a hundred kinds of
28.equal one pound.
A.Ten 2 pence coinsB.Twelve 5 pence coins
C.Ten 10 pence coinsD.Three 50 pence coins
29.The phrase run to in the last paragraph means:.
A.reach more thanB.reach less than
C.be reduced toD.reach as much as
30.The word uniform in the last paragraph indicates:.
A.in decimal systemB.unique system
C.Common MarketD.economic ties