文档介绍：非谓语动词
在句中充当除谓语以外的句子成分的动词形式叫做非谓语动词。非谓语动词分为三种形式:不定式、动名词和分词(分词包括现在分词和过去分词)
不定式
不定式的作用
作主语不定式作主语时,谓语用单数。往往用it 作形式主语,把不定式放在谓语后面。如:
It took us two hours to finish the job.
It is impossible for us to get there on time.
It is very kind of you to help us.
注意:(1)其他系动词如look, appear等也可用于此句型。
(2)当不定式作主语的句子中又有一个不定式作表语时,不能用It is …to…的句型。试比较:
It is to negate my own idea to believe him.(错)
To believe him is to negate my own idea .(对)
(3)It is+ adj. of / for sb. to do sth. 结构中,当不定式的逻辑主语和前面的形容词可以构成系表结构时,用of, 否则用 for.
作宾语
动词+不定式。如:
He managed to escape from the fire.
I find it hard to get along with him.(it 作形式宾语)
注:下列动词通常用不定式作宾语:want, try, hope, wish, need, forget, know, promise, refuse, help, decide, begin, start, learn, agree, choose, get等
动词+疑问词+to , “特殊疑问句+不定式”相当于名词,作宾语。如:
I don’t know what to do next/ how to do it next.
I can’t decide when to go there.
注意:不定式短语作宾语时,如果还带有宾语补足语,往往把不定式短语放在宾语补足语之后,用it 作形式宾语。如:I find it necessary to learn a foreign language.
作宾语补足语
动词+宾语+不定式(to do )。如:
He warned me to be careful.
I want you to speak to Tom.
What makes you think so?(不带to的不定式)
注:可以用动词不定式做宾补的动词有:ask, tell, order ,want ,get, would like, like, advise, invite, allow, help, wish,warn, expect, prefer, encourage
表见解、看法的动词结构可为:动词+宾语+ to be 的不定式结构。如:
We consider Tom to be one of the best students in our class.
The book is believed to be useful.(被动语态)
(3) There +不定式。如:
W