单选题
The Natural Balance Being Altered

The balance of nature is a very elaborate and delicate system of check and countercheck. It is continually being altered as climates change, as new organisms evolve, as animals or plants spread to new areas. But the alterations have in the past, for the most part, been slow. whereas with the arrival of civilized man, their speed has been multiplied much: from the evolutionary time-scale where change is measured by periods of ten or a hundred thousand years, they have been transferred to the human time-scale in which centuries and even decades count.
Everywhere man is altering the balance of nature. He is facilitating the spread of plants and animals into new regions. Sometimes deliberately, sometimes unconsciously. He is covering huge areas with new kinds of plants, or with houses, factories, slagheaps and other products of his civilization. He gets rid of some species on a large scale, but favors the multiplication of others. In brief, he has done more in five thousand years to alter the biological aspect of the planet than has nature in five million years.
Many of these changes which he has brought about have had unforeseen consequences. Who would have thought that the throwing away of a piece of Canadian waterweed would have caused half the waterways of Britain to be blocked for a decade? Or that provision of pot cacti for lonely settlers' wives would have led to Eastern Australia being covered with forests of prickly pears?
Who would have predicted that the cutting down of forests on the Adriatic coast, or in parts of Central Africa, could have reduced the land to a semi-desert with the very soil washed away from the bare rock? Who would have thought that improved communications would have changed history by the spreading of disease- sleeping sickness into East Africa, measles into Ocean, AIDS around the whole world?
These are spectacular examples, but examples on a smaller scale are everywhere to be found. We made a nature sanctuary for rare birds, providing absolute security for all species; and we may find that some common and hardy kind of birds multiplies beyond measure and drive away the rare kinds in which we are particularly interested. We see, owing to some little change brought about by civilization, the starting spread over the English countryside in hordes. We improve the yielding capacities of our cattle; and find that how they exhaust the pastures which were sufficient for less demanding stock. We gaily set about killing the carnivores that disturb our domestic animals, the hawks that eat our fowls and game-birds; and find that in so doing we are also removing the brake that restrains the multiplication of mice and other little rodents that gnaw away the farmers' profits.
单选题 The author's concern with the balance of nature, as evidenced by this passage, is best defined as ______.
  • A. intense and objective
  • B. conscientious but humorless
  • C. sincere and subjective
  • D. deep but dry
【正确答案】 A
【答案解析】[解析] 作者开篇即提出了人类以前所未有的速度打破了自然平衡的观点之后，就紧紧围绕这一论点，列举了大量客观发生的事例集中阐述，从中可以看出，作者的论述是客观的，选项A很好地表达了作者这一态度，其他三个选项B“尽责的但缺乏幽默感”；C“真挚主观”；D“深入枯燥”在原文中都找不到依据。
单选题 So far as the alterations of the balance of nature are concerned, man ______.
  • A. is somewhat more responsible than nature itself
  • B. plays a much greater role than nature itself
  • C. has done more than nature in recent years
  • D. is more likely to blame than nature
【正确答案】 B
【答案解析】[解析] 文章第二段最后一句提到，“In brief, he has done more in five thousand years to alter the biological aspect of the planet than has nature in five million years.”表明在对自然平衡的改变方面，人类比自然界所起的作用要大，即B项中的内容。通过这句话同样可以判断出A、C、D不正确。A中不应是“somewhat”，C中不应有“in recent years”，D中不应是“likely”，而是确实如此。
单选题 It can safely be inferred from the article that ______.
  • A. civilized man is No. 1 enemy of nature
  • B. altering the balance of nature will definitely lead to man's extinction from the planet
  • C. modem technology sometimes makes people's life worse rather than better
  • D. most deserts and senti-deserts are due to the cutting down of forests
【正确答案】 C
【答案解析】[解析] 原文第四和第五段列举了大量的事例来说明人类对自然界平衡的破坏，导致了一系列严重的后果。选项C较为确切地表达出了这一层意思，而其他三项都过于绝对，在原文中没有根据。
单选题 This passage can best be characterized as ______.
  • A. a reminiscence of times past
  • B. a thoughtful essay on nature's laws
  • C. a lament that so many species vanished
  • D. an objective discussion of civilization
【正确答案】 B
【答案解析】[解析] 作者在文中论述的中心就是人类通过自身的活动打破了自然平衡，为自己带来了严重后果，所以我们可以说本文是一篇关于自然法则的富有思想的文章。A“对过去的回想”，D“关于文明的客观讨论”不是本文主要内容。作者提到了大量物种的消失，但从文中并看不出作者在“哀悼”，所以C“为许多消失的物种哀悼”不合适。
单选题 The word "unforeseen" (Line 1) in Paragraph 3 means ______.
  • A. that have never been seen
  • B. that have never been experienced
  • C. that cannot be accepted
  • D. that cannot be expected
【正确答案】 D
【答案解析】[解析] “unforeseen”的词义一是可以从其本身的构词特征上着手，我们应该能够猜出foresee的意．思是“预见”，那么unforeseen应该就是“难以预见的”。另一方面，我们可以从作者在下文中不断运用的“who would have thought predicted...”句式中猜测其义，这是一种虚拟表达方式，表示“谁能想得到或预见到……”。也就是说，作者所依据的例子都是一些事先想不到的或无法预见的后果。