公共英语五级-39及答案解析.doc

1、公共英语五级-39 及答案解析(总分：100.00，做题时间：90 分钟)一、Section Listening (总题数：0，分数：0.00)二、Part A(总题数：1，分数：5.00)You will hear a talk. As you listen, answer Questions 1 to 5 by writing T (for True) or F (for False). You will hear the talk ONLY ONCE. （分数：5.00）(1).Fleming finished his studies in 1906.（分数：1.00）A.正确B.错误(

2、2).Fleming was a doctor of a mobile medical group during World War .（分数：1.00）A.正确B.错误(3).After World War I, Fleming was appointed a professor at St. Mary“s Hospital.（分数：1.00）A.正确B.错误(4).Fleming discovered penicillin quite by accident.（分数：1.00）A.正确B.错误(5).The great value of penicillin was recognized

3、soon after its discovery.（分数：1.00）A.正确B.错误三、Part B(总题数：2，分数：6.00)Questions 1 3 are based on the following passage; listen and choose the best answer. （分数：3.00）(1).What are the thirteen hundred men and women preparing to do?（分数：1.00）A.They are going to remove dust particles.B.They are going to perfor

4、m operations on patients.C.They are going to shoot scenes for a science fiction film.D.They are the technicians who make the latest computer and Intel Pentium chips.(2).Why do these people walk through air showers?（分数：1.00）A.There is strong wind.B.Blasts of air remove dust particles from their cloth

5、ing.C.They have an air-conditioner installed.D.It is very hot.(3).What“s next in the high-tech world of computer chips?（分数：1.00）A.Dust-free circuits.B.Smaller computers.C.Faster chips.D.Less-powered computers.Questions 4 6 are based on the following passage; listen and choose the best answer. （分数：3.

6、00）(1).What is the advantage of CD over plastic records?（分数：1.00）A.It is new.B.It plays on a machine that uses laser light to reproduce the music.C.It can hold a great amount of information.D.It is used with the computer.(2).What has the Britannic Software Company recently produced?（分数：1.00）A.A real

7、 book.B.A disc.C.A machine used with the computer.D.Compton“s Modem Media Encyclopedia.(3).What does Compton“s Modem Media Encyclopedia provide?（分数：1.00）A.Different sounds.B.Many pictures.C.Written information.D.A, B and C.四、Part C(总题数：1，分数：5.00)You will hear a talk. As you listen, you must answer Q

8、uestions 1 5 by writing NO MORE THAN THREE words. （分数：5.00）(1).What did Bell“s determination result in?（分数：1.00）_(2).What did Bell do when he was young?（分数：1.00）_(3).When did Bell finally solve the problem of sending human speech over an electric wire?（分数：1.00）_(4).What was the first sentence ever s

9、poken over the telephone?（分数：1.00）_(5).Why were all the telephones in North America silenced on August 2, 1922?（分数：1.00）_五、Section Use of Eng(总题数：1，分数：30.00)The more time scientists spend designing computers, the more they marvel at the human brain. Tasks that stump the most advanced supercomputer 1

10、 a face, reading a handwritten note are child“s play for the 3-Ib. 2 . Most important, unlike any conventional computer, the brain can learn 3 its mistakes. Researchers have tried for years to program computers to 4 the brain“s abilities, but without success. Now a growing number of designers believ

11、e they have the answer: if a computer is to 5 more like a person and less like an over-grown calculator, it must be built more like a brain, which distributes information across a vast interconnected web of 6 cells, or neurons. Conventional computers function by following a chainlike sequence of det

12、ailed 7 . Although very fast, their processors can perform only 8 task at a time. This approach works best in solving problems that can be broken down into simpler logical pieces. The processors in a neural-network computer, by contrast, 9 a grid much like the nerve cells in the brain. Since these 1

13、0 neurons are interconnected, they can share information and perform tasks at the same time. This two-dimensional approach works best at recognizing patterns. Instead of 11 a neural-network computer to make decisions, its makers trains it to recognize the patterns in any solution to a problem 12 rep

14、eatedly feeding examples to the machine. Neural-network computers come in all shapes and sizes. 13 now most existed as software simulations because redesigning computer chips 14 a lot of time and money. By experimenting with different approaches through 15 rather than hardware, scientists have been

15、able to avoid costly mistakes.（分数：30.00）六、Section Reading Co(总题数：0，分数：0.00)七、Part A(总题数：1，分数：10.00)It is hard to predict how science is going to turn out, and if it is really good science it is impossible to predict. If the things to be found are actually new, they are by definition unknown in advan

16、ce. You can“t make choices in this matter. You either have science or you don“t and if you have it you are obliged to accept the surprising and disturbing pieces of information, along with the neat and promptly useful bits. The only solid piece of scientific truth about which I feel totally confiden

17、t is that we are profoundly ignorant about nature. I regard this as the major discovery of the past hundred years of biology. It is, in this way, an illuminating piece of news. It would have amazed the brightest minds of the 18th century Enlightenment to be told by any of us how little we know and h

18、ow bewildering seems the way ahead. It is this sudden confrontation with the depth and scope of ignorance that represents the most significant contribution of the 20th century science to the human intellect. In earlier times, we either pretended to understand how things worked or ignored the problem

19、 or simply made up stories to fill the gaps. Now that we have begun exploring in earnest, we are getting glimpses of how huge the questions are, and how far from being answered. Because of this, we are depressed. It is not so bad being ignorant if you are totally ignorant; the hard thing is knowing

20、 in some detail the reality of ignorance, the worst spots and here and there the not-so-bad spots, but no true light at the end of the tunnel nor even any tunnels that can yet be trusted. But we are making a beginning, and there ought to be some satisfaction. There are probably no question we can th

21、ink up that can not be answered, sooner or later, including even the matter of consciousness. To be sure, there may well be questions we can“t think up ever, and therefore limits to the reach of human intellect, but that is another matter. Without our limits, we should be able to work our way throug

22、h to all our answers, if we keep at it long enough, and pay attention.（分数：10.00）(1).Which of the following is NOT true about really good science according to the passage?（分数：2.00）A.People can“t foresee how it will turn out.B.It involves surprising pieces of information.C.It is the major discovery of

23、 the past hundred years of biology.D.It will produce results which are unknown in advance.(2).Which of the following can be inferred from the passage about the scientists of the 18th century?（分数：2.00）A.They thought they were ignorant.B.They thought they had little bewilderment in science.C.They avoi

24、ded solving scientific problems.D.Their efforts were harmful to the human intellect.(3).Which of the following is NOT true about scientists in earlier times?（分数：2.00）A.They falsely claimed that they knew almost everything about nature.B.They paid little attention to the problems which bewildered the

25、m.C.They invented theories to explain some phenomena.D.There was nothing that they couldn“t think up.(4).The author“s attitude toward science is _.（分数：2.00）A.confidentB.doubtfulC.depressedD.regretful(5).The author holds that _.（分数：2.00）A.there are no limits to the reach of human intellectB.the matte

26、r of consciousness is beyond the scope of scientific researchC.man will sooner or later solve all the problems he can think upD.there are no questions man can“t think up八、Part B(总题数：1，分数：10.00)A good many technical people become angry when you call a computer a giant brain. They insist that computer

27、 does only what thinking humans have planned to have it do. 1 There is a popular anecdote about a computer programmer who, just for a good fun, spent days setting up the machine to destroy itself, then watched delightedly as the computer dutifully proceeded to commit suicide. If that machine could h

28、ave thought, would it not have got the better of him? 2 Apparently, neurons are elementary memory units, capable of storing the same kind of information “bits“ that a machine can store. The completely materialistic view is that neurons, along with an extraordinary network of nerve-communication line

29、s, comprise all there is to the brain. But such an explanation fails to account for how the brain originates thought. 3 Computers can already do a lot of surprising things, which include predicting the weather. The machine is able to make forecasts by absorbing vast quantities of data, but this, as

30、well as most of the other tasks now performed by the thinking machines, is routine, requiring thinking of a very low order. Let us see what happens when we go beyond this step. A great many outstanding men are preoccupied with computers that do nonnumerical work: that is, machines that go on from th

31、ere after all the figures are in. These men want to see, for example, whether lifeless devices can exercise judgment, make choices, give birth to ideas, and play games intelligently. At the far limit of possibility, they wish to know whether, at least on paper, machines can reproduce themselves. In

32、other words, are we really certain that a machine can do only what its programmer wills it to do? Already there are in existence a number of machines that approach these powers. The simplest type is the computer that understands logic. 4 Boolean algebra caught the eye of two Harvard students some ye

33、ars ago, and they built a machine called the Logical Truth Calculator. It created quite a stir in Cambridge, because it worked extremely well at solving rather simple logical problems. Soon more complicated machines were developedmachines that could play games. The mechanical game-players fall into

34、a number of classes. The simplest has a dictionary of rules in its memory, including all possible moves to be made in answer to an opponent. A second class plays only according to a strict formula, and can never lose. 5 Dr. Claude Shannon of Bell Telephone Laboratories, and his colleague, E. F. Moor

35、e, once built a machine to play the game known as Hex, using an analog computer working on electrical voltages. “It beat them about 70 per cent of the time. It frequently surprised its designer,“ Shannon comments, “by selecting odd-looking moves which, on analysis, proved sound!“ A. To me the contro

36、versy boils down to a definition of the word “think“. There is no area in physiology that is less understood than the human brain. Practically all that is known is that the brain contains some ten billion tiny cells called neurons. B. Probably the clearest difference between man and machine is a qua

37、ntitative one. The brain has roughly a million times as many parts as the best computer. On the other hand, the difference may lie in a spiritual factor, embraced by religion. At any rate, a machine cannot exercise free will or originate anythingnot yet. Whether it ever will is still an open argumen

38、t. C. A third category applies the principles of approximations, choosing the probable best move by “thinking“ over all imaginable moves and testing each against a certain standard. The games these machines can play include checkers, chess, bridge, poker, and many other card games. They can“t always

39、 win, because an approximately right move isn“t necessarily the best one, but few human opponents can do better. D. The mathematics of logic, upon which such machines work, was originated a century ago by an obscure Englishman named George Boole. Boolean algebra, as it is now called, has proved to b

40、e of great service to telephone engineers in designing automatic switching apparatus. E. But complexity is not the only requirement: the billions of parts would all have to work together to produce reliable results. Considering how far from perfect most human brains are, there isn“t much threat from

41、 a synthetic one. F. Yet one authority states categorically, “A machine can handle information: it can calculate, conclude, and choose, it can perform reasonable operations with information. A machine, therefore, can think.“ Famed mathematician Norbert Wiener, of MIT, foresees a machine that can lea

42、rn will “in no way be obliged to make such decisions as we should have made, or will be acceptable to us.“ Evidently, he thinks machines can think.（分数：10.00）九、Part C(总题数：1，分数：20.00)A=Wind Power B=Coal-Fired Power C=Nuclear Power Which Power. can bring about ash which contains heavy metals? 1 is the

43、only energy-producing industry which takes full responsibility for all its waters? 2 does not deplete our natural resources? 3 can be produced by the fuels which can even be transported by aircraft? 4 does not produce carbon dioxide or other greenhouse gases? 5 contributes to acid rain and snow? 6 i

44、s expected to be the cheapest source of electricity available? 7 has significant environmental implications? 8 produces carbon dioxide which is expensive to remove or reduce? 9 is considered promising concerning carbon dioxide emissions? 10 Wind Power Wind energy has been harnessed by man for at lea

45、st 4,000 years. About 1,400 years ago Persians were using wind energy to grind grain. By 1800, there were an estimated 500,000 windmills in Europe and China. Wind power also played an important role in settling the Great Plains. In 1930 more than 600,000 windmills were at work in the U.S., pumping w

46、ater and producing electricity. Electricity from the wind is clean, renewable, and inexhaustible. Nothing is burned or “used up“ to produce wind power. Using wind power in place of coal, natural gas, or oil avoids the environmental impacts of mining, drilling, transporting and burning these fuels. I

47、t does not deplete our natural resources. No land must be strip-mined to extract it. Furthermore, wind power does not pollute the air or water, does not create hazardous waste, and does not produce carbon dioxide or other greenhouse gases. It does not threaten the earth“s climate. We have an incredi

48、ble opportunity to create a cleaner environmental future for ourselves, our children and our communities. It“s wind power-and it“s up to us! Wind farms may harm birds. At some sites, particularly Altamont Pass in California, wind turbines have caused a regrettable increase in deaths of birds, including hawks and eagles. But today“s newer wind farms are sited to avoid such conflicts. For example, the National