新概念英语语法:状语从句
http://yingyu.yinghuaedu.com 来源:英华教育(青岛)语言中心 发布时间:2012-12-24 15:25:13
状语从句是副词性从句,它在句子中担任状语,修饰主句的动词、形容词或副词。根据修饰的方面,状语从句可以分为以下九种:时间状语从句、地点状语从句、原因状语从句、目的状语从句
1.时间状语从句
1.when指的是“某一具体的时间”。whenever指的是“在任何一个不具体的时间”。
When I came into the room, he was writing a letter.
当我进屋时,他正在写信。
We shall go there whenever we are free.
我们什么时间有空,我们就去那里。
2.when意为“这时”或“在那个时候”,可以看作是并列句,这种用法的when分句一般位于句末。
I was walking along the street when suddenly someone patted me on the shoulder from behind.
我正在街上走着,这时忽然有人从后面拍我的肩膀。
3.while指“在某一段时间里”,“在……期间”,while引导的动作必须是持续性的。
While it was raining, they went out.
天下雨的时候,他们出去了。
I stayed while he was away.
他不在的时候我在。
4.as引导持续性动作,强调主句和从句的动作同时发生。
He hurried home, looking behind as he went.
他赶快回家,不时地一边走一边向后看。
5.before译为在……之前
Be a pupil before you become a teacher.
先做学生,再做先生。
6.after译为在……之后
He arrived after the game started.
比赛开始后,他到了。
7.如主句动词是持续性动作,常用肯定式,表示“直到……为止”。从属连词为till/until
We waited till (until) he came back .
我们一直等到他回来。
8.如主句动词是瞬间动词,常用否定式,表示“直……才”“在……以前不”,从句放在句首表示强调,一般用until
She didn’t stop working until eleven o’clock.
她到11点钟才停止工作。
Until he had passed out of sight, she stood there.
她站在那里看着,直到看不见他的身影。
9.hardly…when和no sooner…than的意义相当于as soon as,但只表示过去发生的事情,主句为过去完成时,从句为过去时,如hardly或no sooner位于句首时语气强,而且主句的谓语要用部分倒装。
I had hardly got home when it began to rain.
我刚一到家,就下雨了。=Hardly had I got home when it began to rain.
No sooner had we got to the station than the train left.
我们刚到车站,火车就走了。
Hardly had we begun when we were told to stop.
我们刚开始就被叫停。
10.在时间状语从句中,不能用将来时或过去将来时,而要用现在时或过去时代替将来时。
Every time I travelled by boat, I got seasick.
我每次乘船都晕船。
The moment I heard the song, I felt cheerful.
我一听到这首歌,就感到很愉快。
Next time you come, you’ll see him.
下次你来的时候,就会见到他。
11.状语从句在主句之前时一般用逗号与主句分开,从句在主句之后则不必用标点符号。
Great changes have taken place in China since 1978.
自从1978年以来中国发生了巨大的变化。
As soon as I arrive in Shanghai, I’ll write to you.
我一到上海就给你写信。
2.条件状语从句
1.unless从句的谓语只能用肯定式。unless和if…not同义,unless是书面语,if…not是口语,通常二者可以换用。
条件状语从句中的谓语动词的时态一般要用现在时或过去时代替一般将来时或过去将来时。从属连词为if, unless, as/so long as, in case, so far as。
Difficulties are nothing if we are not afraid of them.
如果我们不怕困难,困难就算不了什么了。
We shall go there tomorrow unless it rains.
除非下雨,我们明天就去那里。
= We shall go there tomorrow if it doesn’t rain.
So/As long as you work hard, you will succeed.
只要你努力工作,你就一定能成功。
In case I forget, please remind me about it .
万一我忘了,请提醒我一下。
So far as I know, the book will be published next month.
据我所知,那本书下月出版。