B. The Two Definitions of Dinosaurs C. How to Clone the Extinct Animals D. Scientific Research on Dinosaurs 正确答案：A 得分：2分
23. According to the passage, \
A. maximize B. raise C. continue D. minimize 正确答案：D 得分：2分
24. Scientists are warning governments around the world that ____.
A. the number of Giant pandas is decreasing due to the shrinking of their natural habitat
B. the current rate of extinction is more than million times above normal C. one fourth or more species are facing the danger of extinction D. B and C 正确答案：C 得分：2分
25. The former elephant hunters now find that they can earn big money from ____.
A. keeping elephant domestically B. selling ivory
C. ecology-associated tourism D. making souvenir trinket
正确答案：C 得分：2分
Passage Two
Biological diversity has become widely recognized as a critical conservation issue only since the past two decades. The rapid destruction of the tropical rain forests which are the ecosystems with the highest known species diversity on Earth has awakened people to the importance and fragility of biological diversity. The high rate of species extinctions in these environments is jolting, but it is important to recognize the significance of biological diversity in all ecosystems. As the human population continues to expand, it will negatively affect one after another of Earth's ecosystems. In terrestrial ecosystems and in fringe marine ecosystems (such as wetlands), the most common problem is habitat destruction. In most situations, the result is irreversible. Now humans are beginning to destroy marine ecosystems through other types of activities, such as the disposal and runoff of poisonous waste; in less than two centuries, by significantly reducing the variety of species on Earth, they have unraveled cons of evolution and irrevocably redirected its course.
Certainly, there have been periods in Earth's history when mass extinctions have occurred. The extinction of the dinosaurs was caused by some physical event, either climatic or cosmic. There have also been less dramatic extinctions, as when natural competition between species reached an extreme conclusion. Only 0.1 percent of the species that have lived on Earth have survived to the present, and it was largely chance that determined which species survived and which died out.
However, nothing has ever equaled the magnitude and speed with which the human species is altering the physical and chemical world and demolishing the environment. In fact, there is wide agreement that it is the rate of change humans are inflicting, even more than the changes themselves, that will lead to biological devastation. Life on Earth has continually been in flux as slow physical and chemical changes have occurred on Earth, but life needs time to adapt — time for migration and genetic adaptation within existing species and time for the proliferation of new genetic material and new species that may be able to survive in new environments.
26. Which is the best title of the passage?
A. The Variety of Species
B. The Rapid Destruction of the Tropical Rain Forest C. Species' Adaptation to New Environment
D. The Impact of Human Activities on Earth's Ecosystems 正确答案：D 得分：2分
27. According to the passage, how do humans destroy marine ecosystems?
A. Through shipping a lot of goods.
B. Through disposal and runoff poisonous waste. C. Through destroying Earth's ecosystem. D. Through hunting fish. 正确答案：B 得分：2分
28. What determines which species survived and which died out?
A. Slow chemical changes. B. Impact of human activities. C. Chance.
D. Some physical event. 正确答案：C 得分：2分
29. What will lead to biological devastation?
A. Climatic or cosmic event. B. Chemical change.
C. The rate of change humans are inflicting. D. Physical change. 正确答案：C 得分：2分
30. The natural evolutionary change is different from change caused by humans in that it ____.
A. is irreversible
B. affects the ecosystem
C. occurs at a faster rate D. occurs at a much slower rate 正确答案：D 得分：2分
Vocabulary and Structure
Directions: Each of the following sentences is provided with four choices. Choose the one that best completes the sentence. (60 points)
31. The twentieth century has witnessed an enormous worldwide political, economic and cultural ____.
A. transportation B. tradition C. transmission D. transformation 正确答案：D 得分：2分
32. He made outstanding contributions in the ____ of foreign affairs.
A. realm B. region C. reality D. referee 正确答案：A 得分：2分
33. He was eager to begin the new day and ____ sadness by his strong will and strong arm.
A. submit B. subdue
C. surrender D. subway 正确答案：B 得分：2分
34. I should assign you your share of labour, and ____ you to accomplish it.
A. complete B. compare C. compensate D. compel 正确答案：D 得分：2分
35. You can ____ from this bus to bus NO 24.
A. transmit B. transform C. transfer D. convert 正确答案：C 得分：2分
36. But they also say that even with today's ____ science, the DNA is right.
A. important B. imperfect C. deficit D. import 正确答案：B 得分：2分
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