有关as作连词的用法

有关as作连词的用法

一．as引导状语从句

as作为连词可以引导状语从句，表示时间、原因、方式、让步等。

1. 引导时间状语从句，意思是“当``````的时候”，同when/while,更强调“一边``````一边``````”。表“随着``````”的意思时同with,但with是介词，不可以跟从句。

eg: I saw him as he was getting off the bus.

He often listens to the music as he is doing his homework.

As time goes by, his illness is getting worse.

2. 引导原因状语从句，同since。

eg: We had better hurry as it is getting dark.

As she has no car, she can’t get there easily.

有关as作连词的用法

一．二．as引导定语从句

1. as引导限制性定语从句。

as作为关系代词可以引导限制性定语从句，通常与the same或such连用，构成the same ``````as和such``````as句型。

eg: I have never heard such stories as he tells.

This is the same dictionary as I lost.

有关as作连词的用法

要用倒装结构。可以把从句中表语、状语甚至谓语动词置于句首，如果是带有冠词的可数名词单数作表语，置于句首时应省去冠词。

eg: Young as he is, he knows a lot about history.

Much as I like you, I will not marry you.

Try as she might, Mary couldn’t get the door open.

Boy as he is, he is very shy. (boy前省略冠词a)

4. 引导方式状语从句，表示方式。意思是“像，按照，如同”。

eg: Do it as I do it.

You should finish your task as you are told to.

Leave it as it is.

有关as作连词的用法

2. as引导非限制性定语从句。

as与which一样都可以引导非限制性定语从句，但是as引导的从句可以放在主句之前、主句之后，甚至还可以分割主句；而which引导的非限制性定语从句只能放在主句之后。另外as还有“正如、就像”之意。

eg: As is mentioned above, the number of the students in senior high schools is increasing.

He was admitted to college, which made his parents very happy.

John, as you know, is a writer.

动词不定式

动词不定式是非谓语动词的一种，它没有人称和数的变化，在句子中不能独立作谓语，但它仍保持动词的特点，既可以有自己的宾语和状语。

动词不定式的构成：

to+动词原形

动词不定式作主语

动词不定式作主语时句子有以下两种

(1)把不定式置于句首。如：

To get there by bike will take us half an hour.

(2)用it作形式主语，把真正的主语不定式置于句后

It will take us half an hour to get there by bike.

常用句式有

①It＋be＋名词＋to do

It‘s our duty to take good care of the old.

②It takes sb+some time+to do

How long did it take you to finish the work?

③It＋be＋形容词＋for sb＋to do

It is difficult for us to finish writing the composition in a quarter of an hour.

④It seems＋形容词＋to do

It seemed impossible to save money

动词不定式作宾语

后面能接不定式作宾语的动词有：agree, ask, choose,

decide, forget, hope, learn, want, wish, would like

等。如：

We hope to get there before dark. 我们希望天黑以前到那儿。

The girl decided to do it herself. 那个姑娘决定自己做那件事。

动词不定式作宾语的注意事项（2点）

1．有些动词既可跟不定式作宾语，也可跟动名词作宾语，但含义不同：remember to do 记住要做某事；remember doing 记得曾经做过某事

forget to do忘记要做某事forget doing 忘记曾经做过某事

stop to do 停下来去做某事stop doing 停止做某事

go on to do 继续做另一件事go on doing 继续做原来在做的事

I remember seeing you somewhere before.

我记得以前在哪儿见过你。

Please remember to turn off the light when you leave.

离开时请记得关好灯。

2．不定式作宾语时，如带有宾语补足语，则要把不定式放到后面，用it作形式宾语，构成“主语+动词+it+宾补（形容词、名词）+不定式”结构。如：

He found it very difficult to get to sleep.

他发现很难入睡。

动词不定式作宾语补足语

1．后面能接to不定式作宾语补足语的动词有：ask, order, teach, tell, want, wish, help 等。

The teacher told us to do Exercise 1.

老师要我们做练习一。