[单项选择]What social scientists have long felt puzzled about is why ______.


A. the mortality rate can not be predicted
B. the death toll remained stable year after year
C. a quota for each type of death has not come into being
D. people lost their lives every year for this or that reason

[单项选择]What social scientists have long felt puzzled about
A. The mortality rate can not be predicted.
B. The death toll remained stable year after year.
C. A quota for each type of death has not come into being.
D. People lost their lives every year for this or that reason.

[单项选择]John ______ from social activity because he felt embarrassed with people.


A. held on
B. held back
C. held off
D. held out

[单项选择]Social scientists have recently become greatly interested in space because ______.


A. space industrialization will create new markets and more jobs on Earth
B. space exploration will be harmful to man
C. space colonization is near at hand
D. otherwise technologists will catch the opportunity to go to space

[单项选择]According to her, what was the most difficult about becoming a taxi driver


A. The right sense of direction.
B. The sense of judgment.
C. The skill of maneuvering.
D. The size of vehicles.

[单项选择]

Text 3
Lately social scientists have begun to ask if culture is found just in humans, or if some animals have culture too. When we speak of culture, we mean a way of life a group of people have in common Culture includes the beliefs and attitudes we learn. It is the patterns of behavior that help people to live together. It is also the patterns of behavior that make one group of people different from another group.
Our culture lets us make up for having lost our strength, claws, long teeth, and other defenses. Instead, We use tools, cooperate with one another, and communicate in language. But these aspects of human behavior, or "culture", can also be found in the lives of certain animals.
We used to think that the ability to use tools was the dividing line between human beings and other animals. Lately, however, we have found that this is not the case. Chimpanzees can not only use tools but actually make tools themselves. This is a major s
A. some animals may also have the same ability to use language as human beings
B. human beings, unlike many other animals, no longer have such features as great strength, claws, long teeth and other defenses
C. there seems to be nearly no difference between human beings and other animals
D. monkeys and chimps seem to have more in common with human beings than any other animals