问题 问答题 简答题

液压机构中电接点压力表的作用是什么?

答案

参考答案:

压力表的作用是监视氮气预压力及工作压力。其高压接点或低压接点闭合启动中间继电器,通过中间继电器的接点发出压力异常信号,并将油泵电机回路切断,低压接点的中间继电器同时切断开关的分、合闸控制回路,以防低压力下分、合闸,造成事故扩大。

阅读理解

根据两封信的内容,选择正确答案。

Dear editor

  I'm not a good-looking boy and I'm not good at studying. Some people don' t

even want to talk to me.  So I usually feel lonely.  Sometimes I think that if I want

ed to leave home,  nobody would care. How can I stop feeling like this?

Peter

Dear Peter

  Without knowing more about you, it is hard for me to give you some good

advice. But first, I am sure that you are wrong that nobody would care if you left

home.  What about your parents? And other family members?  It seems that you

are very sad. You' d better talk to your parents. They will be able to help you.  

Second,  I'm sure there's someone in your class who feels lonely, too.  You never

know how other people feel inside.  Try to make friends with them.  Or you may

join a club to meet new people and to keep yourself busy. You need to find

happiness in yourself. Write a list of all the good things about yourself. Learn to

like yourself, and then others will see your confidence(自信心) and like you,

too.

Your friend

1. What' s the trouble with Peter?

A.He doesn't like his parents.

B. He doesn't like others.

C. His parents don't like him.

D. He isn't good at studying and feels lonely.

2. Why does Peter write to the editor?

A. Because he wants to make friends  with him.

B. Because he wants to ask the editor to  help him.

C. Because he wants the editor to know  about him.

D. Because he wants to give the editor  advice.

3. If Peter joins a club, he can _____.

A. meet new people and make friends  with them

B. keep his friends busy

C. study hard but never think about others

D. become g good-looking boy

4. What does the editor's first advice tell  Peter to do?

A. To see a doctor

B. To talk to his parents

C. To talk with his teacher

D. To help others

5. Peter will probably (很可能) feel _____ when he reads the letter from the

editor.

A. sad          

B. lonely      

C. glad      

D. afraid

单项选择题