题目内容
Section B
Directions: In this section, you will hear 3 short passages. At the end of each passage, you will hear some questions. Both the passage and the questions will be spoken only once. After you hear a question, you must choose the best answer from the four choices marked A, B, C and D.
听力原文： Animal experiment is the base of American research and treatment of disease Each year，17 million to 22 million animals are sacrificed in the name of science While 90 percent of them are rats and mice．180,000 dogs, 50，000 cats，61，000 monkeys and 554, 000 rabbits are done away with in laboratories operated by industry and government(26)But the public has raised a protest over these deaths．They've documented cases in winch monkeys were isolated in steel tanks for 45 days and dogs were bombed with radiation or chemicals Scientists say such incidents are rare. Laws have been passed to govern testing．Many research centers now have committees to review all animal experiments，and computers can be used in place of animals in many experiments．(27) But scientists say they can't do without animals to test new drugs and treatments on animals to make sure they're safe for humans．Animal experiments produced treatments for diseases Animal rights activists have shown they will go to almost any length．One New York researcher received more than 10．000 protest letters following Publicity of her experiments in which she gave drugs to monkeys．The battle between scientists and activists raises a basic question：Can modern society be both humane in its treatment of living things and advanced in its treatment of disease？ (28)It seems certain there will be new restrictions placed on the use of animals in scientific experiments．
(27)
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听力原文：W: Would you please give us a morning call tomorrow morning？
M: Certainly, sir. A morning call at 6: 45 tomorrow morning and your luggage will be collected at 7:45. Is that all right？
Q: Where does the conversation most probably take place？
(16)
If man continues to interfere with the balance of nature, it is possible that ______ may soon become extinct.
The balance of nature is a delicate system of checks and counter-checks. Nature has its own way of checking the life and distribution of the different organisms and helping their growth. An epidemic may be considered nature's way of checking population growth. Man in his attempt to conquer nature and to utilise it to his advantage has interfered with the balance of nature, thereby creating problems of a complex nature. Nature's ways of maintaining the balance are intricate and not easily understood and man's application of his scientific knowledge and techniques has upset this balance so much that today, being aware of the disastrous consequences, he takes measures against them.
No animal or plant can live in isolation, for different organisms are parts of a vast dynamic complex of living things. As no man. or community is serf-sufficient, no organism can live by itself. When man interferes with the interdependence and interrelationships of the different organisms, he is, in effect, upsetting their balanced relationships and his action can have a chain reaction. If we prevent fish eggs from being deposited in a pond, we are allowing an unchecked growth of weeds. The waterfowl which feeds on tadpoles will look for alternatives, thereby tending to upset these blanced relationships. It is important that for the preservation of beauty in nature the balance of nature is maintained.
Man for his own survival has to make his peace with plant and animal life, the size and distribution of which he has interfered with. It is to be noted that in every plant and animal community there is a trend towards a balance between the different species. When each successive species is of. the right number to maintain a constant population, a balance between the different species is maintained and this state is referred to as the climax stage. Man is forever upsetting the balance of the climax stage. He has added to the numbers of animals and plants that are useful to him. In the process he has unwittingly helped the increase in the number of insects and vermin and as a result he has to wage a relentless war against them. if man continues to interfere with the balance of nature, it is possible that some animals and birds may soon become extinct. The indiscriminate hunting of whales has reduced the number of some species almost to the verge of extinction and international laws have been drawn up to protect them.
The balance of nature is to be maintained in order to prevent soil deterioration. Human intervention has altered the established relationship between the plants of an area and the soil of that area. Animals introduced by man, sheep and goats for example, have led to widespread soil deterioration. By cutting down trees or by practising unsuitable systems of agriculture, man destroys the crumb structure of soil, thereby making it susceptible to erosion. Soil erosion results in loss of soil fertility and maintaining soil fertility is considered the biggest problem facing mankind apart from the prevention of war. The increase in world population and the growth of civilisation have been the two major factors that have led man to cut down forests on an unprecedented scale and the erosion caused by the cutting down of huge areas of forests has resulted in floods on a scale hitherto unknown. Soil erosion can whittle away soil fertility and if adequate and effective measures are not taken it can become a menacing spectre tearing at the prosperity of many countries.
Pollution, in its different forms, interferes with the balance of nature. Water pollution affects nature's balance in oceans, lakes and rivers. Man-made pollution of water is due to municipal sewage, dumping by factories and the depositing of pesticides. Solid wastes can permeate the soil and pollute lakes and rivers.
Man has to adopt the philosophy of thrift by conserving natural resources and not destroying the
Much of the holiday spending is on gifts for others. At the simplest level, giving gifts involves the giver thinking of something that the recipient would like—he tries to guess her preferences, as economists say—and then buying the gift and delivering it. Yet this guessing of preferences is no mean feat; indeed, it is often done badly. Every year, ties go unworn and books unread. And even if a gift is enjoyed, it may not be what the recipient would have bought had they spent the money themselves. Intrigued by this mismatch between wants and gifts, in 1993 Joel Waldfogel, then an economist at Yale University, sought to estimate the disparity in dollar terms. In a paper that has proved seminal in the literature on the issue, he asked students two questions at the end of a holiday season: first, estimate the total amount paid (by the givers) for all the holiday gifts you received; second, apart from the sentimental value of the items, if you did not have them, how much would you be willing to pay to get them？ His results were gloomy: on average, a gift was valued by the recipient well below the price paid by the giver. The most conservative estimate put the average receiver's valuation at 90% of the buying price. The missing 10% is what economists call a deadweight loss: a waste of resources that could be averted without making anyone worse off. In other words, if the giver gave the cash value of the purchase instead of the gift itself, the recipient could then buy what she really wants, and be better off for no extra cost. If the results are generalized, a waste of one dollar in ten represents a huge aggregate loss to society. It suggests that in America, where givers spend $40 billion on Christmas gifts, $4 billion is being lost annually in the process of gift-giving. Add in birthdays, weddings and non-Christian occasions, and the figure would balloon. So should economists advocate an end to gift-giving, or at least press for money to become the gift of choice？
Why do some people regard the holiday season in western economies a treat？
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