单项选择题

Passage Three
Questions 33 to 35 are based on the passage you have just heard.

A. How they interacted with modern humans.
B. Whether they lived alongside with modern humans.
C. How they came to grow so small.
D. How they ended up disappearing from the earth.

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单项选择题

What makes Candace Bracken’s anger spark her to fight against the disease

A. The diagnosis of acute leukemia.
B. Nobody could take care of her kid if she dies.
C. The bone marrow transplant is unnecessarily suffering.
D. A doctor told her to find someone to look after her baby.

填空题

It is clear that some chemicals can damage the health of animals and humans. However, this is not the only problem that can be caused by the (36) use of chemicals. Chemicals can also (37) the ecological balance of the environment. If the ecological balance is broken, the (38) can be extremely serious. The history of DDT (39) the problem. DDT, a chemical which kills insects, at first, seemed to be a perfect answer to many problems. It would control insects that caused dangerous diseases, as well as insects that made (40) of dollars of damage to crops every year. Governments (41) and even encouraged the use of DDT. Farmers in many countries began to spray it on their crops. The (42) results were good: Damage to crops went down, and profits went up. However, the chemical had (43) which the scientists did not predict. First, (44) . Second, and perhaps worse, DDT did not kill every harmful insect. (45) . In a few years there were large numbers of insects which were not affected by DDT. Finally, it became clear that DDT was not solving the insect problem. In fact, (46) !

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