while,when,as用法

1、while, when与与as用法辨析：用法辨析：(1) while引导时间状语从句作引导时间状语从句作“当当时候时候”讲时，只能与讲时，只能与延续性延续性动词连用。动词连用。(2) when引导时间状语从句作引导时间状语从句作“当当时候时候”讲时，既可与讲时，既可与延续性延续性动词也可与动词也可与瞬间动词瞬间动词连连用。用。(3) as强调主从句谓语动词表示的动作强调主从句谓语动词表示的动作同时同时进行进行，意为，意为“一边一边一边一边”。它还有。它还有“随着随着”的意思。的意思。while, when与与as用法辨析：用法辨析：(1) he was reading, he fell asl

2、eep.(2) he came in, I was having lunch. I was sleeping, a thief broke in.(3) He looked behind from time to time he walked. time went by, she became more and more nervous.while的用法的用法 引导时间状语从句引导时间状语从句1. 引导时间状语从句，意为引导时间状语从句，意为“当当时时候候”“”“在在期间期间”。His parents died he was at school.2. 引导时间状语从句，意为引导时间状语从句，意

3、为“与与同时同时”。You may go swimming Im having lunch.3. 引导让步状语从句引导让步状语从句(需置于主句之前需置于主句之前)，意为意为“虽然虽然”“”“尽然尽然”。 Im willing to help, I dont have much time available.4. 用作并列连词，表示前后两个分句之间用作并列连词，表示前后两个分句之间的的对比对比，意为，意为“然而然而”。He likes listening to music, I enjoy watching TV.While 的其他词性 n.一会儿时间 stay for a while. 停留一

4、会儿。 Wait a while. 等一会儿。 The project wasnt worth my while. 这项方案不值得我花工夫。 v.消磨：闲散或轻松地消磨时间 while the hours away.二、二、when的用法的用法1. 引导引导时间时间状语从句：状语从句：at / during / after the time that 在在/当当时；在时；在之后之后I loved maths I was at school. 我在学校时喜欢数学。我在学校时喜欢数学。Call me youve finished.你完成后打电话给我。你完成后打电话给我。 2. 引导引导让步让步状语

5、从句：状语从句：although 虽然，然而，可是虽然，然而，可是Im saying it now I should have told you long ago. 我早就应该告诉你了，可是我现在才说。我早就应该告诉你了，可是我现在才说。3. 引导引导原因原因状语从句：状语从句：considering that考虑到，既然考虑到，既然How can they expect to learn anything they never listen.既然他们从不听讲，他们怎么能指望学到东西呢？既然他们从不听讲，他们怎么能指望学到东西呢？ 4. 引导引导条件条件状语从句：状语从句：if 如果如果 th

6、e weather is good, I usually go to the country. 若是天气好的话若是天气好的话, 我总是到乡下去。我总是到乡下去。 5. 连接并列句：连接并列句：after which; and just then 一一就就，正在这时，正在这时He had just drifted off to sleep the phone rang. 他刚迷迷糊糊地睡下，这时电话铃就响了。他刚迷迷糊糊地睡下，这时电话铃就响了。 三、三、as的用法的用法1. 引导引导时间时间状语从句：状语从句： during the time when; while 在在期间；当期间；当时候时

7、候 she grew older, she kept more to herself. 随着年龄的增长，她变得更沉默了。随着年龄的增长，她变得更沉默了。I was coming in he was going out. 我进来的时候我进来的时候, 他正出去。他正出去。 2. 引导引导原因原因状语从句：状语从句：because; since 由于；因为由于；因为I must stop now I have to go out. 我得就此打住了，因为我得出去我得就此打住了，因为我得出去。 3. 引导引导让步让步状语从句：状语从句：although 尽管，虽然尽管，虽然 Sweet he is, h

8、e doesnt pay his bills. 他虽然和蔼可亲，却不买账。他虽然和蔼可亲，却不买账。 Try he might, he failed to pull it off. 虽然他一试再试，却没有成功。虽然他一试再试，却没有成功。 4. 引导引导方式方式状语从句：状语从句：in the way in which 以以方方式；像式；像一样一样They can do they wish. 他们能随心所欲。他们能随心所欲。 She kissed him goodbye, usual. 她同平常一样和他吻别。她同平常一样和他吻别。 5. 引导定语从句引导定语从句 正如正如 you can see, I didnt go after all. we all know, Zhou Hao is a good Teacher. 你看，我毕竟没有去。你看，我毕竟没有去。 as 引导比较状语从句：as + adj + asas much as not so much as as 作副词：同样 This bo