How much living space does a person need? What happens when his space requirements are not adequately met? Sociologists and psychologist are conducting experiments on rats to try to determine the effect of overcrowded conditions on man. Recent studies have shown that the behavior of rats is greatly affected by space. If rats have adequate living space, they eat well, sleep well, and reproduce well. However, if their living conditions become too crowded, their behavior patterns and even their health perceptibly change. They cannot sleep and eat well, and signs of fear and tension become obvious. The more crowded they are, the more they tend to bite each other and even kill each other. Thus for rats, population and violence are directly related. Is this a natural law for human society as well? Is adequate space not only desirable, but also essential for human survival?(10分)
(1)This passage is mainly about 1 .(2分)
∙ A. living space and behavior
∙ B. population and living conditions
∙ C. interesting experiments on rats
∙ D. a natural law for human society
(2)What is the purpose of the experiments described in the passage?(2分) 3
∙ A. To determine how much living space a rat needs.
∙ B. To see what happens when rats live in a limited space.
∙ C. To know the likely effects of inadequate living space on human beings.
∙ D. To find out the relationship between population and living conditions
(3)Which is NOT a result of being too crowded for rats?(2分) 4
∙ A. They become nervous.
∙ B. They cannot get enough rest.
∙ C. They eat less.
∙ D. They become less active.
(4)The passage suggests that overcrowded conditions 2 .(2分)
∙ A. are directly related with population
∙ B. may cause an increase in violence
∙ C. may lead to high birth rate
∙ D. may bring about pollution problems
(5)The author seems to imply that 3 .(2分)
∙ A. human society is very similar to that of rats
∙ B. birth control is essential for a better life
∙ C. efforts should be made to improve living conditions
∙ D. rats are not social animal

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