题目

你的身体时刻都与周围空气进行气体交换，你呼出的气体在组成成分上发生的变化是 A、氧气含量增加，二氧化碳含量增加 B、氧气含量增加，二氧化碳含量减少 C、氧气含量减少，二氧化碳含量增加 D、氧气含量减少，二氧化碳含量减少 答案：C 阅读理解。      We may know some good health habits, but we don't realize how much difference they can make. In the 1970s, scientists at the University of California-Los Angeles asked 7,000 people about their health habits.Then they followed these people to see how long they lived.     The scientists discovered that seven habits were closely linked with a longer life. ▲eating breakfast every day▲avoiding eating anything like cakes between meals ▲keeping a good weight-not too heavy or too thin ▲exercising regularly ▲sleeping seven or eight hours every night-not more or less ▲not smoking▲drinking two or fewer alcoholic (含酒精的) drinks every day      The researchers found that these habits had a powerful effect on health. People in this study who hadthree or fewer of these habits lived another 21.6 years. People who had six or seven could expect to liveanother 33 years!      But how do you change your habits? Make one small change every week. And be patient. It takes about21 days to form a new habit. 1. The underlined word "they" (Paragraph 1)most probably refers to            . [     ] A. scientists B. good habits C. universities D. 7,000 people 2. One of the habits closely linked with a longer life is            . [     ] A. taking regular exercise B. drinking less water every day C. eating cakes between meals D. sleeping more than eight hours every night 3. The idea "these habits had a powerful effect on health" is supported with            . [     ] A. guesses B. storiesC. experiences D. facts 4. In which page of a newspaper can you most probably read this passage? [     ] A. News B. Health C. Business D. Sports 5. The passage is written mainly to tell people            . [     ] A. to keep a good weight B. to avoid eating to much C. to form good health habits D. to keep away from danger