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助动词be的用法
日期:2020-05-27


助动词be的用法

 

1.  be +现在分词,构成进行时态。如:

They are having a meeting. 他们正在开会。

We were planting trees this time yesterday. 我们昨天这个时候在植树。

2.  be + 过去分词,构成被动语态。如:

The door was broken by Tom. 门是汤姆打破的。

English is taught in our school. 我校教英语

3.  be + 动词不定式,可表示:

A.  打算、决定、计划、安排等。如:

He is to visit Japan next week. 他决定下周访问日本。

I was to have told you yesterday, but you were not in. 我本打算昨天告诉你的,但你不在家。

B.  指示、命令、禁止等,即“必须,一定”。如:

You are to hand in the exercises tomorrow. 你们明天必须交练习。

You’re not to (=You mustn’t)  smoke here. 你不可以在此处抽烟。

C.  责任、义务、需要,即“该不该”。如:

You are to (=should)  report to the police.  你应该报警的。

Am I to go on with the work? 这工作我该不该继续干下去?

D.  可能性,与can, may相当,不定式多用被动式。如:

The book was not to (=could not)  be found. 那本书可能找不到了。

E.  假设,用于虚拟条件句中。如:

If it were to rain, we would get wet. 要是下雨,我们就会淋湿。

F.  表示注定要发生或后来必然发生。如:

This experience was to change his life. 这次经历注定要改变他的生活。

注:不定式作表语与上述用法是不同的。如:

My idea is to go there today. 我的意思是今天就去那里。