问题 选择题

据调查,目前我国18.25亿亩耕地中只有7.5亿亩能确保灌溉,另外10多亿亩的旱耕地,只能依靠自然降水来进行农业生产。这表明,我国水资源已经陷入了“奇缺”的状态。对此,认识正确的有

①水是人类生活中必不可少的资源

②人类的过度消耗和环境污染使水资源奇缺

③淡水资源危机已经是21世纪关系人类生存最严重的危机

④在21世纪,淡水资源危机正在成为一种稀缺资源

A.①②③

B.①②④

C.①③④

D.①②③④

答案

答案:B

水是人类的生命之源。从材料中可得知淡水资源对人类的重要性,但到底是不是最严重的危机,需通过比较才可以知晓。故③不选。

名词解释
阅读理解

阅读理解。

     Compared to adults, children seem to be moving constantly. So it's no surprise that most parents who

are quizzed about their child's physical activity level describe their children as fairly active. But a new

study of nearly 2000 British school children suggests that many parents overestimate the amount of

physical activity their children are really getting.

     The researchers equipped 1892 British school children, ages 9 and 10, with accelerometers that

measure all physical  activity  during  a  given  time  period.  The research, known as the Speedy study

collected the exercise data from children at  92  schools  in  Norfolk, England, between April and July

2007.

     A child was regarded inactive if he or she recorded less than an hour a day of physical activity.

Although the majority of children studied were getting enough physical activity, a sizable minority of

children were not. Overall,39 percent of girls and 18 percent of boys studied were getting less than an

hour of physical activity each day.

     But if you asked the parents of the inactive children to describe their child's activity level, the vast

majority-80 percent-described their children as fairly or very physically active, according to the findings

published in the American Journal of Preventive Medicine. Interestingly, the children themselves had

more awareness about their lack of physical activity. Overall, 40 percent of children overestimated their

physical activity.

     But it wasn't the parents of overweight children who were most likely to guess wrong about physical

activity levels. The parents who were most out of touch about their child's physical fitness were more

likely to  have children who were slim. Parents of girls were also more  likely  to  overestimate  physical 

 activity.  The  researchers noted that parents should be educated about the importance of physical

activity for children even if the child is not overweight.

     "Parents of slim children appear to assume that  their children are adequately active." the study

authors  reported. "Increasing awareness regarding health benefits of physical activity beyond weight

control might  help have a correct idea of physical activity levels and encourage behavior change."

1. According to the Speedy study, what kind of children   can be judged physically inactive?

A. Slim children.

B. Children with less than an hour a day of physical activity.

C. Overweight children.

D. Children out of touch with their parents for a long time.

2.What does the writer probably mean by saying "a sizable minority of children were not" in Paragraph 3?

A. The amount of children's physical activity is far from the writer's satisfaction.

B. Only a small number of children were not getting enough physical activity.

C. A small number of children didn't overestimate their physical activity.

D. The minority of children were not studied at all.

3.The passage is intended to_______.

A. encourage parents to fairly judge their children's physical activity levels

B. persuade parents to keep an eye on their children's weight

C. urge children to wear accelerometers during exercise

D. advise parents to keep in touch with their children