问题 选择题
如图所示为一磁流体发电机示意图,A、B是平行正对的金属板,等离子体(电离的气体,由自由电子和阳离子构成,整体呈电中性)从左侧进入,在t时间内有n个自由电子落在B板上,则关于R中的电流大小及方向判断正确的是(  )

A.I= ,从上向下

B.I= ,从上向下

C.I= ,从下向上

D.I= ,从下向上

答案

答案:A

阅读理解

阅读理解。

      It is said that more than four million people die each year from smoking. That number is frightening.

     Yet people around the world continue to smoke. In the United States, about forty-seven-million adults

smoke. This year, more than 430,000 Americans died of diseases which have something to do with smoking.

The American Cancer Society (美国癌症协会) says smoking harms the body greatly. It warns that smoking

even a number of cigarettes is dangerous.

     It's (3) ______________________________ (戒烟是不容易的.) However, doctors say you probably will

live longer if you do stop smoking. You will feel better and look better. You also will protect the health of

family members who breathe your smoke.

     There is not one right way to stop smoking, doctors say. Any way can help. You can take long walks or

spend time in places where smoking is not allowed. Also, you can eat a small piece of fruit or vegetable instead

of having a cigarette. (4) The sooner you stop smoking, the more you'll reduce (减少) your chances of getting

cancer and other diseases. Stop smoking before smoking stops you!

   根据短文内容,简要回答下列问题。

1. How many people die from smoking each year? 

    _________________________________________________________

2. What does the American Cancer Society say about smoking?

    _________________________________________________________

3.  根据短文中所给汉语完成句子。

     It's ______________________________________________________ 

4.  把短文中划线的句子翻译成汉语。

     _________________________________________________________

5.  给短文拟一个恰当的英文标题。

     _________________________________________________________

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