1、公共英语五级-阅读理解(七)及答案解析(总分：30.00，做题时间：90 分钟)一、练习六(总题数：0，分数：0.00)二、Part A(总题数：0，分数：0.00)三、Text 1(总题数：1，分数：5.00)Koalas, an Australian tree-climbing animal, are very particular about what they eat, devoting themselves entirely to a diet of the leaves of eucalyptus trees. But there are problems associated w
2、ith an exclusive diet of leaves, especially if, like the koala, you happen to be a relatively small animal. One of these problems is that the leaves of trees are rich in fibre, and so resist digestion. Eucalyptus leaves are worse than most, for they contain large amounts of lignin, the indigestible,
3、 woody material found in the cell walls of many plants.But there is another drawback for the koala. The ratio of an animals gut volume to its energy requirements depends on body mass; the smaller it is, the lower the ratio. So tiny leaf-eaters are likely to have difficulty processing sufficient quan
4、tities of their poor-quality food to meet their metabolic needs.S. J. Cork and T. J. Dawson of the University of New South Wales and I. D. Hume of the University of New England have made a study of the koalas digestion. They have identified three major factors that allow koalas to exploit its fibre-
5、laden diet.In the first place, the koala has a discerning digestive system; like the rabbit, it can regulate the passage of food through its gut in a way that discriminates between particles of different sizes. The alimentary canal retains and solutes smaller, more digestible particles, while expell
6、ing unwanted, coarser matter. This is probably a space-saving exercise; it has the effect of increasing the rate at which raw material can be fed into the system.The second factor behind the koalas success is that it has a low overall requirement for metabolic energy, compared to other Australian an
7、imals of similar size. So it saves on its fuel needs. In this respect, the koala is not dissimilar to another slow-moving, leaf eating mammal, the three-toed sloth.Thirdly, eucalyptus leaves have hidden qualities. Despite the large quantity of lignin, such leaves are rich in digestible energy -espec
8、ially in the form of fatty substances. Not all such resources are available to the koalas metabolic machinery; essential oils are passed out, for example. But some fatty substances are available, as are sugar and starch. It is these compounds that satisfy the bulk of the koalas energy needs.Surprisi
9、ngly, constituents of the eucalyptuss cell walls, such as cellulose, are less important. Some cellulose is digested, but the koalas accomplishments in this field do not rival those of other animals that reshow.（分数：5.00）(1).One of the problems of eating too much of tree leaves is that（分数：1.00）A.the l
10、eaves are made of woody materials.B.the leaves are not easily digested.C.small animals need little energy.D.small animals process large amount of food.(2).The purpose of Cork, Dawson and Hume study is to（分数：1.00）A.find out why koalas could digest eucalyptus leaves.B.find out how koalas expel unwante
11、d material.C.compare koalas with other Australian animals of similar size.D.compare eucalyptus leaves with other tree leaves.(3).The word “discerning“ in Line I, paragraph 4 is closest in meaning to（分数：1.00）A.discovering.B.uninteresting.C.understanding.D.discriminating.(4).Eucalyptus leaves are diff
12、erent from other tree leaves in that they have（分数：1.00）A.large quantities oflignin.B.large amounts of fatty substances.C.large amounts of digestible engird.D.large amounts of sugar and starch.(5).The title of the text might be（分数：1.00）A.Why Koalas Like Eucalyptus Leaves.B.Why Koalas Process Food to
13、Meet Their Needs.C.Why Eucalyptus Leaves Are Rich in Digestible Engird.D.Why the Eucalyptus Cell Walls Are Less Important.四、Text 2(总题数：1，分数：5.00)The new-technology revolution in American newspapers has brought increased circulations, a wider range of publications and an expansion of newspaper jobs i
14、n spite of reduced manning in the composing rooms.Payrolls in the publishing industry more than doubled in a decade from $3.1 billion in 1972 to $6.3 billion in 1981. Capital investment, largely as a result of re-equipment with new technology, doubled from $554m in 1972 to $1.02 billion in 1981.Circ
15、ulation of weekly newspapers has grown from 21m in 1960 to 49m in 1985. Big city dailies have remained relatively static, with total circulation going from 58m to 63m. Sunday papers, though, have grown more dramatically from 8.6m to 56m. This reflects the trend toward specialisation. Growth has been
16、 especially strong in the number and circulation of suburban and small-community newspapers. In 1965 there were only 357 semi-weekly papers; in 1982, 508.There has also been a dramatic rise in newspapers circulating nationwide something that hardly existed in the old days. The Wall Street Journal is
17、 producing regional editions that have catapulted it into becoming the nations largest-circulation newspaper, a role formerly held by the New York Daily News. In addition, USA Today and the New York Times have used technological advances, particularly satellite-delivery of pages to regional producti
18、on facilities, to achieve unprecedented growth.A number of daily papers have added Sunday editions -made possible through the new technology in response to demand from advertisers.Total newspaper employment, according to government statistics, rose from 345,000 in 1965 to 443,000 in 1984 and that fi
19、gure does not fully cover the multitude of local papers. But the International Typographical Union, which formerly had a firm grip on nearly all printing jobs, has shrunk from over 100,000 in 1967 to 40,000 today, of whom about 4,000 are in fact retired members. The prospect is that the union may be
20、 reduced to 5,000 members in the near future.According to Jim Cesnik of the 33,000-member journalists union, the Newspaper Guild, employment of journalists has grown but not to the same extent as that of sales people pushing advertising and circulation. The guild, however, has few members on the sma
21、ll local papers.The New York Times spent $2m on radio advertising to boost home-delivery of the paper in the first nine months of 1985 -a campaign responding to a fall in the number of streetside news-stands. The general growth in circulations has helped increase advertising revenue among dailies fr
22、om $15 billion in 1965 to $66 billion in 1982.An interesting development noted by Charles Cole, a consultant to the 1,375-member American Newspaper Publishers Association, is that local newspapers have expanded their news-gathering teams, and some now send people abroad as well as having representat
23、ives in many American cities. Other departments in papers have also advanced, according to Cole. For example, mail rooms of many newspapers employ up to 25% more people handling the national advertising inserts that have become common. However, more automatic machinery may well reduce manning here.（
24、分数：5.00）(1).Which of the following has grown most rapidly in number?（分数：1.00）A.City dailies.B.Sunday papers.C.Weekly newspapers.D.Suburban newspapers.(2).According to the text, which of the following is the largest-circulation newspaper in the United States?（分数：1.00）A.The Wall Street Journal.B.New Y
25、ork Daily News.C.USA Today.D.New York Times.(3).From paragraph 6, we learn that the International Typographical Union（分数：1.00）A.is closing down in the near future.B.is losing its markets to its competitors.C.still controls almost all the printing jobs.D.has a bright future in face of the difficultie
26、s.(4).According to Jim Cesnik, there have been more（分数：1.00）A.advertising radios than the newspapers.B.sales people than the news-stands.C.journalists than the news-stands.D.journalists than sales people.(5).We may infer from paragraph 9 that（分数：1.00）A.local newspapers carry more advertisements.B.re
27、presentatives of local newspapers are not welcomed.C.local newspapers did not send people abroad before.D.manual handling will be replaced by machines.五、Text 3(总题数：1，分数：5.00)A new variety of sugar cane, bred from crosses of ordinary cultivated strains with a wild type found in Argentina, could becom
28、e an important source of energy as well as sugar.Two conditions need to be fulfilled to make it worthwhile to cultivate an agricultural crop for energy. The crop must be easy to harvest and process, and it must be high-yielding. On both these counts, sugar cane is ideal: the technology for harvestin
29、g and milling has been thoroughly tested over the years, and sugar cane is one of the most productive plants ever recorded.Professor Mike Giamalva and his colleagues at Louisiana State University have now produced a plant that is super-productive. Their new variety grows to 3.6 metres high. On exper
30、imental plots, it gives yields of 253 tons per hectare -equal to the highest yield of any plant recorded. But even this record has been exceeded. On good soil, yields may reach 321 tons per hectare.Another advantage of Giamalvas new strain of sugar cane is its high fibre content. Traditionally, rese
31、archers have selected strains that produce large amounts of juice rich in sugar, and low quantities of fibre. The fibre is either discarded, or sometimes burnt as fuel. The new sugar cane gives exceptional quantities of fibre for only modest amounts of juice. When it comes from the mill, the bagasse
32、 has about 70 per cent of the heat content of wood, or 30-40 per cent of that of coal.Burning bagasse to provide energy is not a new idea. Many sugar factories throughout the world are now self-sufficient in energy, while some, for example, in Mauritius, Hawaii and South Africa, “export“ electricity
33、 to the national grid. Mauritius currently gets around 10 per cent of its electricity from sugar factories.However, in Louisiana local farmers are unwilling to grow the cane until they have a guaranteed market. Yet industrialists will not invest in the new fuel until they have a constant supply. And
34、 only local factories may be able to exploit cane because, being bulky, it is costly to transport. One way of overcoming this problem would be to dry the fibrous residue and compact it. Work on compacting fibrous residue is now under way in several research centres. Whether compacting will pay its w
35、ay will depend on the local situation and the cost of alternative energy supplies. A study carried out by Fay Baguant from the University of Mauritius showed that electricity could be produced there from fibrous residue about twice as cheaply as from oil or coalfired stations.The new variety can be
36、grown with ordinary sugar cane or with other crops to provide energy for processing. It can be compressed and burned as a substitute for charcoal. Or it can be incorporated into paper, cardboard and fibreboard. Brazil, with its fleet of cars running almost entirely on alcohol fuel extracted from sug
37、ar cane, already has shown that the plant has the potential to alter radically a countrys agricultural sector.（分数：5.00）(1).How does sugar cane meet the two conditions of cultivating an agricultural crop for energy?（分数：1.00）A.It is highly productive and easy to be harvested.B.It is high yielding and
38、easy to be transported.C.It is the highest yielding crops so far.D.It is worthwhile to grow the crops.(2).What is special of Mike Giamalvas new sugar cane?（分数：1.00）A.It is high yielding and nutritious.B.It has been recorded.C.It is high yielding and rich in fibre.D.It has fibre residue.(3).Why are L
39、ouisiana farmers reluctant to grow sugar cane?（分数：1.00）A.Because they dont know how to transport it to factories.B.Because they are not sure if they can sell their crops.C.Because no industrialists are willing to use cane as fuel.D.Because local factories have bought them all.(4).What does“bagasse“
40、in line 6, paragraph 4 mean?（分数：1.00）A.cane roots.B.sugar juice.C.cane leaves.D.fibrous residue.(5).The writers attitude towards the potentials of the new sugar cane is（分数：1.00）A.pessimistic.B.doubtful.C.optimistic.D.understandable.六、Part B(总题数：1，分数：5.00)One of the greatest economic and social chang
41、es of the post-war years has gone largely unnoticed. It is that more and more women are going out to work. Today in the United States, in Japan and in the United Kingdom, almost 40 per cent of the work force is female.16. _Most women now work far longer hours than men -in factory, shop or office as
42、well as in the home as cook, cleaner, child rearer, shopper and home-maker. This “double burden“ means that the average woman who goes out to work is now putting in an 80-hour working week -twice as long as most men.So equality depends not only on women sharing in paid employment but also on men sha
43、ring in the tasks of the home. At the moment husbands in all industrialised countries contribute very little to domestic work and recent research shows that this contribution does not increase when the wife goes out to work. American researcher Joan Vanek, for example, found that the average father
44、in the United States spends only 12 minutes a day with his children. Overall, womens unpaid work in the U.S. A. is estimated at about 40 per cent of the Gross Domestic Product.17. _The reasons why women earn less than men go deeper than legislation. And again the main cause is the double burden of h
45、ome responsibilities which means that many women have to take part-time jobs, or less demanding jobs, and that they have less time for training and less opportunity for promotion.As children, girls are educated and conditioned either for no employment at all or for more manial and lower-paid jobs. A
46、s workers, they are crowded into industries like textiles, food, clothing, retailing -where they compete with each other for low-paid and insecure jobs which require little skill or training and offer little chance of promotion. A recent survey in Sweden shows that women have a choice of about 25 di
47、fferent occupations whereas a man chooses from over 306 careers. Indeed certain countries, says the OECD, “have come to rely on a supply of female labour which costs little and enjoys little protection“.18. _Single parent families are increasing in almost every industrialised country. In Britain at
48、least 600,000 families are now headed by single mothers and the number is growing by 6 per cent a year. The main cause is the rise in divorce rates which have doubled in many countries during the last 15 years.19. _As the ILO notes, pensioners are the poorest social group in the industrialised world
49、. But here too it is the women who are worst off -partly because they tend to live longer than men and partly because inequality during their working lives is reflected in reduced pensions. In the United States, for example, the 8 million women who are over the age of 65 make up by far the poorest group of people in America -with almost half of them living below the official poverty line.20. _The first half of the U.N. Decade for Women has now gone and the vast majority of women in the industrialised countries have seen little or no benefit. Equal-pay
