不带to的动词不定式

不加to的不定式

http://zhidao.baidu.com/question/1514405.html

主要是感官动词和使役动词

五看：look at/see/watch/observe/notice

三让：let/make/have

二听：hear/listen to

一感觉：feel

http://wenku.baidu.com/view/a16eb9d184254b35eefd3464.html

 

不定式是动词的非限定形式之一，非常活跃的语言现象。不带to的不定式（bareinfinitive）非常普遍，主要用在情态动词和助动词will，shall，would，should,can，could，might，must。。。以及在作为情态动词的need和dare之后。这点极易掌握，不再赘述。除此以外，在下列情况也要使用不带to的动词不定式。

1    在see，feel，hear，watch，observe，listento，look at，notice等感官动词或短语以及let, have,make等表示祈使意义的动词之后：不定式做宾语补足语不能带to；help后的不定式可以带，也可以不带；know在一定的条件下，后面的不定式做宾补时可以不带to。例如

I saw the man come out of the house.    查找和宾语从句的区别

I heard her say that she was from Japan.

We felt the house shake.

They watched the sun sink into the sea.

Did you notice him stop?

They did not observe Jim come in and go upstairs.

She was listening to him climb the stairs.

Look at the boy run.

I’ll let you know as soon as I hear from her.

I had him mend my watch.

Electricity makes motors run.

He helps me (to) plant trees.

I have never known him sing so beautifully.

不带to的动词不定式跟在上述动词后面时，情况复杂，一下几个问题需要特别注意：

1） 当上述句子变成被动语态时，原来做宾补的不定式则相应地成为主语补足语。这时，不定式要加to。以以上句子为例：

The man was seen to come out of the house.

She was heard to say that she was fed up.

后面的句子以此类推。英语中有一条规律：凡是被动的动词都不能和不带to的不定式连用。只有let除外，原因是做主语补足语的不定式是单音节词。例如

The students were let go after class.

The grass was let grow.

 

2) 不定式在help之后，既可以做宾补，也可以直接做宾语，例如：

This book will help (to) improve your English.

Help之后不定式带to和不带to有以下几种区别：a）不带to在非正式文体中更常见。B）不带to的不定式在美国英语比在英国英语中常见。C）决定不定式带不带to主要涉及主语，如果主语不能参与到不定式的动作中去，则不定式通常带to，例如

This book helps to see the truth。

This book will help you to use English。

 

3）  have known 后面的不定式可以不带to，也可以保留to，例如

I have known her (to) lie.

Never knew 和have never known的后面通常跟不带to的不定式，偶尔也有带to的不定式，例如 

I never knew him do anything without a good reason.我知道,他做什么事都有理由的。

I have never known him say this before.

I have never known her to tell lies.

 

4) 如果在feel，know，observer，see后面跟的不定式是be，则to不可以省略。例如

We all felt that to be the highest praise.

We know him to be brave.

The only thing that I have observed to be without limit is thebusinessman’s desire for profits.

Now I saw him to be the man who walked up the hill everymorning.

应该注意到的是feel和see在上述例句中已经不是感觉动词，他们的意思分别是“认为”、“以为”和“知悉”、“了解”。

 

2  在口语中，用在祈使句或者不定式go或come后面的不定式有时口语省略to，例如

Go ask him。

Why not call John and ask him to come have dinner with us？

 

3 有时在besides的后面也可以跟不带to的不定式，例如

That afternoon I had nothing to do besides answer letters.

 

4 why在疑问词中是唯一能不用助动词便可以引导疑问句的。其结构为why+不带to的不定式或why not +不带to的不定式。两种结构都是疑问句的形式，却分别表示不同的意思。前者通常用来表明做某事是愚蠢的或者无意义的，意思为“干嘛要。。。”，后者实际是用来提出建议或者劝告，意思为“何不。。。”“干嘛不。。。”。例如

Why stand up if you can sit down?

Why not go here with them?

 

5  had better, had best, would rather, wouldsooner （宁愿）, would as soon（宁愿） 后面跟不带to的不定式

You’d better get some sleep.

You had best get home before midnight.

I would rather not go out tonight, if you don’t mind.

I’d sooner stay at home.

I would as soon as it by myself.

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不加to的不定式

http://zhidao.baidu.com/question/1514405.html

主要是感官动词和使役动词

五看：look at/see/watch/observe/notice

三让：let/make/have

二听：hear/listen to

一感觉：feel