问题 名词解释

选配

答案

参考答案:选配就是有目的、有计划地组织种公母畜的配对,它是有意识地组合后代的遗传基础,以达到通过培育而获得良种的目的。

阅读理解

阅读理解。

     Many children think mobile phones are cool. They come in fun colours and let you talk with a friend

anytime and anywhere.

     In the U.S., more than 90 million people use mobile phones. Many of those people are children. For

children, mobile phones are more than phone calls. They are fashionable.

Most mobile phone users don't think about the health problems caused by mobile phones. Some scientists

say that mobile phones give off radiation (辐射) that might be bad for users. One recent study shows that

mobile phone radiation might raise a person's chance of getting some kinds of cancer (癌症). Other

scientists say mobile phones don't threaten people's health. They say that they have not found any link (联系) between mobile phone use and cancer.

     Scientists say that people can protect themselves from mobile phone radiation. One way is to use a

headset (耳机). Or people can make shorter calls.

1. Many children like mobile phones to _____.

A. show off

B. communicate

C. talk with someone in a faraway place

D. play with electronic things

2. Many of the mobile phone users in the U.S. are _____.

A. girls

B. boys

C. scientists

D. children

3. Which of the following sentences is TRUE?

 A. All scientists think mobile phones are bad for users.

B. Some scientists think mobile phones are bad for users.

C. Mobile phones are only good to grown-up.

D. Mobile phones are only bad for children.

4. The underlined words "give off" in the passage means _____.

A. 发出

B. 放弃

C. 拒绝

D. 传播

5. To protect themselves from radiation, people can _____.

A. talk longer on the phone

B. use a headset

C. talk less on the phone

D. both B and C

问答题 简答题