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不定式的句法功能归纳

2020-06-16来源:和谐英语

 

六、不定式做状语

不定式做状语,可表示动作的目的、结果、原因、条件和方式。

A. 表目的

表目的时,不定式可放在句子的前面也可放在句子的末尾。但在句子前面时,不定式常与句子用逗号隔开;而在句子末尾时一般不用逗号隔开。如:

To get there on time, we set out at five in the morning. 为了按时到达那儿,我们早晨五点就出发了。

He goes there to enjoy the fresh air. 他去那儿享受那儿的新鲜空气。

比较:to do, in order to do, so as to do都可表示目的,但to do, in order to do的位置既可在句首,又可在句末;而so as to do只能在句末(from www.hxen.net)。

In order to build a house, he bought some wood and steel yesterday. —He bought some wood and steel yesterday in order to build a house. / He bought some wood and steel yesterday so as to build a house. 为了建房,昨天他买来了木料和钢材。

B. 表结果

不定式在下列结构中表示谓语动作的结果,不定式的位置一般在句子末尾。

(1) 表示终结性的动词find, see, hear, learn, discover的不定式,常表示出乎意料的结果,并且,不定式前常有never, only等副词修饰。如:

I hurried to the railway station yesterday, (only) to find that the train had left. 昨天我急急忙忙赶到火车站时,发现火车已经开走了。

I went to the classroom, to discover it empty. 我走到教室,结果发现教室是空的。

(2) 在 “so + adj. / adv. + as + to do”中。如:

The scenery is so beautiful as to attract many people here every year. 景色非常美,每年都要吸引很多人来这里。

(3) 在 “adj. / adv. + enough + to do”中。如:

He ran fast enough to catch up with Li Lei. 他跑得很快,结果赶上了李蕾。

(4) 在 “so + adj. / adv. +a(n) + n. + as + to do”中。如:

This is so interesting a story as to interest children. 这是个很有趣的故事,使孩子们非常感兴趣。

(5) 在 “such + adj. / adv. + n. + as + to do”中。如:

She is such a good girl to help you make great progress. 她是个非常好的姑娘,帮助你取得了很大的进步。

(6)  在 “too + adj. / adv. + to do”中。如:

They went too slowly to catch the early bus. 他们走得太慢了,结果没能赶上早班车。

C. 表原因

不定式表示原因时,一般放在句子的末尾,说明主语某种心情、情感(glad, pleased, sad, worried, sorrow, excited) 所产生的原因。如:

I’m very glad to hear that Li Lei has been elected secretary of the Party. 听说李蕾被选为了党的书记,我很高兴。

D. 表条件

不定式表示条件时,一般放在句首。如:

To be heated, liquid will change into gas. 如果受热,液体就会变成气体。

E. 表方式

不定式可接在as if / as though之后表示方式时,如(from www.hxen.net):

He moved his mouth as if to say something. 他的嘴唇动了动,好像要说什么事似的。

七、不定式做同位语

不定式可用作同位语,说明某些名词或代词task, idea, thought的内容。不定式做同位语时,在名词或代词与不定式之间常用逗号隔开。如:

Suddenly I have got the idea, to hunt rabbits in the woods. 突然,我有了这个想法,去林子里去猎取野兔子。

八、不定式做独立成分

To tell you the truth, I don’t like it. 告诉你实话,我不喜欢它。