Question

助动词的用法

Answer 1

助动词用法如下：

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。

English is becoming more and more important. 英语变得越来越重要。

2）be+过去分词，构成被动语态。如：

The window was broken by Tom. 窗户被Tom打破了。

be+动词不定式

1）表示最近、未来的计划或安排。如：

He is to go to New York next week. 他下周要去纽约。

We are to teach the fresh persons. 我们要教新生。

但应注意：这种用法也可以说是一种将来时态的表达法。

2）表示命令。如：

You are to explain this. 对此你要作出解释。

He is to come to the office this afternoon. 他今天下午要来办公室。

3）表示征求意见。如：

How am I to answer him? 我该怎样答复他？

Who is to go there? 谁该去那儿呢？

4）表示相约、商定。如：

We are to meet at the school gate at seven tomorrow morning.

我们明天早晨7点在校门口集合。

have的用法

一、have作助动词

主要变化形式：have，has，had

动名词/现在分词：having

1）have +过去分词，构成完成时态，例：

He has left for London.　他已去了伦敦。

By the end of last month， they had finished half of their work.

上月末为止，他们已经完成工作的一半。

I have been studying English for ten years.

我一直在学英语，已达十年之久。

3）have/has+been +过去分词，构成完成时态的被动语态，例：

The sports meet has been put off until n-ext Friday.

运动会已经推迟到下周五了。