[推荐]when, while ,as soon as |
| [日期：2007-12-07] |
来源： |
作者：admin |
[字体：大 中 小] |
when, while ,as soon as
这三个词都有"当……时候"之意，但用法有所不同，使用时要特别注意。
①when意为"在……时刻或时期"，它可兼指"时间点"与"时间段"，所引导的从句的动词既可以是终止性动词，也可是持续性动词。如：
When I got home, he was having supper.我到家时，他正在吃饭。
When I was young, I liked dancing.我年轻时喜欢跳舞。
②while只指"时间段"，不指"时间点"，从句的动词只限于持续性动词。如：
While I slept, a thief broke in.在我睡觉时,盗贼闯了进来。
辨析
①when从句与主句动作先后发生时，不能与while互换。如：
When he has finished his work, he takes a short rest.每当他做完工作后，总要稍稍休息一下。(when = after)
When I got to the cinema, the film had already begun.当我到电影院时，电影已经开始了。(when=before)
②when从句动词为终止性动词时，不能由while替换。如：
When he came yesterday, we were playing basketball.昨天他来时，我们正在打篮球。
③当从句的谓语是表动作的延续性动词时，when, while才有可能互相替代。如：
While / When we were still laughing, the teacher came in.正当我们仍在大声嬉笑时，老师进来了。
④当从句的谓语动词是终止性动词，而且主句的谓语动词也是终止性动词时,when可和as通用，而且用as比用when在时间上更为紧凑，有"正当这时"的含义。如：
He came just as (or when) I reached the door.我刚到门那儿，他就来了。
⑤从句的谓语动词如表示状态时，通常用while。如：
We must strike while the iron is hot.我们应该趁热打铁。
⑥while和when都可以用作并列连词。
Mike is tall while his brother is short.迈克的个子很高，然而他弟弟很矮。
Mary was on her way home when two big boys stopped her.玛丽正走在回家的路上，这时两个大个子男孩拦住她。
as soon as的用法：
（1）、as soon as one can
= as soon as possible 表示“尽可能快”之意，如：
① You must ring me up as soon as you can.
你必须尽快给我打电话。
② Please write to me as soon as possible.
请尽早给我写信。
（2）、as soon as 引导时间状语从句，表示“一……就……”。如果主句用将来时或情态动词或祈使句，从句必须用一般现在时代替将来时。如：
I’ll tell him the news as soon as he comes.
他一来我就告诉他那消息。
She may come as soon as she finishes the work.
事情一做完她就可以来。
|
阅读：18 次
|
| 【 推荐 】
【 打印 】 |
上一篇：
下一篇：[推荐]经典句 |
