单选题To save the wild species from extinction, the author put the stress on __________.A knowledgeB techniqueC persistenceD confidence

第1题

The loss of biological diversity has become most spectacularly noticeable in extinction or decline of populations of large and well-known animals.Many animal species have become extinct since the 1700’s, among them the California grizzly bear, the dodo, and the passenger pigeon.Hundreds of other animal species are threatened.In North America, endangered species include the black-footed ferret, the California condor, the desert tortoise, and the whooping crane.Most species in danger of extinction anywhere in the world are suffering from the intrusion (侵入) of human beings.The Asian elephant, for example, has become an endangered species due to the expansion of the human population throughout its range in southern Asia.In Africa, the African elephants are being killed off for their tusks.Monkeys and other primates throughout the world are threatened by hunting, capture for medical use, and the destruction of their habitats.And the rhinoceroses, lions, and other large mammals of the African savanna (grassy plains with scattered trees) compete for land and life with some of the most rapidly growing human populations in the world.The loss of biological diversity is most severe, however, in the tropical rain forests.The forests of the tropics are particularly vulnerable to disturbance because the soils have a low capacity for retaining nutrients.Most of the forests’ nutrient elements are held in the tissues of plants.When loggers and farmers destroy existing plant cover, the nutrients are washed from the land into streams, and the land itself becomes less able to support life.Destruction of these forests destroys the habitat of hundreds, sometimes thousands, of species from such creatures as the howler monkey and indigo macaw, to less visible species of plants, insects, and microbes, many of which are not yet known to science.1.The author points out that species extinction ().A.is most noticeable in North AmericaB.is mainly taking place among large animalsC.quickened with industrialization of the societyD.never took place before the 1700’s2.Which of the following is NOT mentioned with regard to human intrusion?A.Elephants are killed off for their tusksB.Some primates are hunted for medical useC.Growing human population results in the competition for land and life among animalsD.Men live increasingly on animals as their source of food.3.The chief cause of the gradual disappearance of biological diversity is ().A.human crueltyB.human interferenceC.the increase of human populationD.the disappearance of the forests4.In tropical forests，().A.animals live a hard life due to competitionB.a lot of species die out for lack of foodC.rains constitute the major threat to speciesD.a greater number of animals are yet to be known5.It can be inferred that species extinction ().A.proceeds of a faster rate than noticeableB.is the worst among well-known animalsC.is the most severe in AfricaD.is chiefly due to competition among species

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第2题

This may have preserved the elephant from extinction as well as other animals () in Africa.A、huntedB、huntingC、that huntedD、are hunted

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第3题

在FoxPro中，要把当前屏幕画面存入内存变量PM中，应当使用的命令是( )。A．RESTORE SCREEN FROM PNB．SAVE SCREEN TO PUC．SAVE ALL TO PUD．SESTORE FROM PU

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第4题

要查询book表中所有书名以“电子商务”开头的书籍作者，可用(61)语句。A.SELECT author FROM booK WHERE book _name=‘电子商务*’B.SELECT author FROM booK WHERE book _name LIKE‘电子商务*’C.SELECT author FROM booK WHERE book_ name=‘电子商务%’D.SELECT author FROM booK WHERE book_name LIKE‘电子商务%’

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第5题

From the fifth paragraph we can infer thatA．the author has never been afraid of changes in his lifeB．the author used to believe that changes happened automaticallvC．the author is still not satisfied with his present situationD．the author and experienced a period of frustration of his life

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第6题

He dived from the bridge to rescue the drowning child.A:help B:drag C:find D:save

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第7题

There was a ___ rush to get everything ready for the unexpected inspection from the superiors.A.calm B.mad C.frantic D.wild

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