动词不定式用法讲解

动词不定式的用法讲解

一、动词不定式：

构成：to +动词原形（to只是不定式符号，没有意义）动词不定式作主语较长时，常用it作形式主语，而将真正的主语放在句末。

1.It + is/was+形容词+(for sb.) +动词不定式

To learn English wellis useful. = It’s useful to learn English well.学好英语是有用的。

To protect environmentis important for us.

= It’s important for usto protect environment.对于我们来说保护环境是很重要的。

2. It is / was + kind / good/ nice/ clever + of sb. +动词不定式

It’s very kind of you to help me.你帮助我真是太好啦。

It’s very clever of you to do li ke that.你那样做真的太聪明啦。

3. It takes ( took , will take ) sb. some time to do something. (做某事花费某人…时间)

4.It is a good idea to do sth.

作宾语

1.常见的跟不定式作宾语的动词有：

want to do sth.decide to do sth.

hope to do sth.plan to do sth.

offer to do sth.agree to do sth.

learn to do sth try to do sth prefer to do sth

promise to do sth.need to do sth.expect to do sth.

2.主语+ find / think+ it +形容词+ (for sb.) + to do

I find it easy to read English every day.我发现每天读英语和容易的。

He felt it hard to sleep.他觉得很难入睡。I think it very interesting to learn English.我认为学英语很有趣。

We found it impossible to cross the river.我们发现过河是不可能的。

3.特殊疑问词+动词不定式作宾语

Can you tell me how to get to the post office?

I didn’t knowwhat to do next.

动词不定式作宾语补足语：

1.ask sb to do sth.tell sb to do sth.

invite sb to do sth want sb to do sth

wish sb to do sth order sb to do sth advise sb to do sth

allow sb to do sth wait for sb to do sth

The question is difficult to answer.这个问题很难回答

The room is comfortableto live in.这个房间住起来很舒服

He is easy to get along with.他很容易相处

I’m glad to see youaga in.很高兴再次见到你

She told me to buy a ticket.她让我去买张票

2.要省去to.

注意:宾语补足语：补充说明宾语的。宾语和宾补之间有逻辑的主谓关系。

He told me to leave at once.

He made the baby laugh.

跟省to的不定式的动词(感使动词)：

一感feel

二听listen to, hear

三使make, let, have

四看look at, watch, see, notice

五半帮助help

The teachers helped the students (to) learn English well.那些老师帮助学生学好英语。

He often helps his mother(to) tidy up the room.他经常帮助他妈妈整理房间。

作表语，表示主语的“职业、职责或性质”

Her job is to clean the hall.她的工作就是打扫大厅。

My dream isto be a teacher.我的梦想是当一名教师。

作定语

动词不定式修饰名词或代词，起形容词的作用，在句中作定语，特点：①.要放在被修饰的名词或代词之后。

I have a lot of books to read.Would you like something to eat?作状语

He worked day and night to get the money.（表目的）他日夜工作来赚钱。

(too...to...,和...adj/adv enough to do sth)（表结果）

She is too young to go to school.

She isn't old enough to go to school.

They were very sad to hear the news.（表原因）听到这个消息他们非常伤心。

The question is simple for him to answer.（表程度）这个问题对他来说太容易回答了。

不定式的否定式是在不定式前加not

They told us not to play basketballtoo long.

You had better not go to bedlate.

动词不定式练习

1.He came ________ (give) us a talk yesterday.

2.She is always the last ______ (come).

3.Tom promised ________ (attend) the meeting.

4.He was lucky enough _______ (find) a seat.

5.Li Ming was too excited ______ (say) a word.

6.The boss made them __ (work) the whole night.

7.His job is _____ (look) after the animals in the zoo.

8.My dream is _____ (fly) to the moon one day.

9.It’s kind ______ you _______ me.

A.of, helping

B.of , to help

C.for, helping

D.for, to help

10.It’s hard _____ (of, for) us _____ (learn) English well.

11.I tried ______ (not make) any noise.

12.I need _______ (practise) speaking more English.