B. Of course, there is some evidence to show this is true.
C. There is hardly any scientific evidence to support this.
D. We don't know because the information is not given.
答案：C细节题。答案在第一段第二和第三句话,“To many people, the cause is obvious: they eat too much But scientific evidence does little to support this idea因此几乎没有任何科学家依据证明这一点”。
4. In comparison with the adult American population today, the Americans of the 1910s __________.
A. ate more food and had more physical activities
B. ate less food but had more activities
C. ate less food and had less physical exercise
D. had more weight problems
答案：A细节题。答案在第一段。“Going back to the America of the 1910s, we find that people were thinner than today, yet they [ate more food.] In those days people [worked harder physically]” 题干中[worked harder physically]相当于答案中had more physical activities。
5. Modem scientific researches have reported to us that__________.
A. fat people eat less food and are less active
B. fat people eat more food than slim people and are more active
C. fat people eat more food than slim people but are less active
D. thin people run less, but have greater increase in food intake
答案：A细节题。答案在第一段。“Going back to the America of the 1910s, we find that people were thinner than today, yet they [ate more food.] In those days people [worked harder physically]” 题干中[worked harder physically]相当于答案中had more physical activities。
Passage 2
Questions 6 to 10 are based on the following passage:
By adopting a few simple techniques, parents who read to their children can greatly increase their children's language development. It is surprising but true. (77) [How parents talk to their children makes a big difference in the children's language development. If a parent encourages the child to actively respond to what the parent is reading, the child's language skills increase].
A study was done with 30 three-year-old children and their parents. Half of the children participated in the experimental study; the other half acted as the control group. In the experimental group, the parents were given a two-hour training session in which they were taught to ask open-ended questions rather than yes-or-no questions. For example, the parent should ask, "What is the doggie doing?" rather than "Is the doggie running away?" (78) [The parents in the experimental group were also instructed in how to help children find answers, how to suggest alternative possibilities and how to praise correct answers].
At the beginning of the study, the children did not differ in measures of language development, but at the end of one month, the children in the experimental group showed 5.5 months ahead of the control group on a test of verbal expression and vocabulary. Nine months later, the children in the experimental group still showed an advance of 6 months over the children in the control group.
