when后面加什么时态,when后面接的哪个时态的从句?



先看when引导的是什么从句,是宾语从句还是时间状语从句 如果是宾语从句,那么时态问题就参考宾语从句的做法 如果是时间状语从句,则基本有4种

when后面加什么时态,when后面接的哪个时态的从句?

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when后面加什么时态,when后面接的哪个时态的从句?

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when后面加什么时态,when后面接的哪个时态的从句?

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2.表示将来的事情,用主将从现(主句将来时,从句一般现在时) 如:I will tell him when he comes back.
3.表示过去两个有先后的动作,都用过去式 如:When he came back,I told him the news.
4.表示一个动作正在进行(过去进行时),另一个动作插入(过去式) 如:I met my teacher when i was walking in the street.
体你可以参考这一段 。
when,while,as引导时间状语从句的区别
when,while,as显然都可以引导时间状语从句,但用法区别非常大 。
一、when可以和延续性动词连用,也可以和短暂性动词连用;而while和as只能和延续性动词连用 。
① Why do you want a new job when youve got such a good one already?(get为短暂性动词)你已经找到如此好的工作,为何还想再找新的?
②Sorry,I was out when you called me.(call为短暂性动词)对不起,你打电话时我刚好外出了 。
③Strike while the iron is hot.(is为延续性动词,表示一种持续的状态)趁热打铁 。
④ The students took notes as they listened.(listen为延续性动词)学生们边听课边做笔记 。
二、when从句的谓语动词可以在主句谓语动作之前、之后或同时发生;while和as从句的谓语动作必须是和主句谓语动作同时发生 。
1.从句动作在主句动作前发生,只用 when 。
①When he had finished his homework,he took a short rest.(finished先发生)当他完成作业后,他休息了一会儿 。
②When I got to the airport,the guests had left.(got to后发生)当我赶到飞机场时,客人们已经离开了 。
2.从句动作和主句动作同时发生,且从句动作为延续性动词时,when,while,as都可使用 。
①When /While /As we were dancing,a stranger came in.(dance为延续性动词)当我们跳舞时,一位陌生人走了进来 。
②When /While /As she was making a phonecall,I was writing a letter.(make为延续性动词)当她在打电话时,我正在写信 。
3.当主句、从句动作同时进行,从句动作的时间概念淡化,而主要表示主句动作发生的背景或条件时,只能用 as 。这时,as常表示“随着……”;“一边……,一边……”之意 。
① As the time went on,the weather got worse.(as表示“随着……”之意)
② The atmosphere gets thinner and thinner as the height increases.随着高度的增加,大气越来越稀薄 。
③As years go by,China is getting stronger and richer.随着时间一年一年过去,中国变得越来越富强了 。
④The little girls sang as they went.小姑娘们一边走,一边唱 。
⑤The sad mother sat on the roadside,shouting as she was crying.伤心的妈妈坐在路边,边哭边叫 。
4.在将来时从句中,常用when,且从句须用一般时代替将来时 。
①You shall borrow the book when I have finished reading it.在我读完这本书后,你可以借阅 。
②When the manager comes here for a visit next week,Ill talk with him about this.下周,经理来这参观时,我会和他谈谈此事 。
三、when用于表示“一……就……”的句型中(指过去的事情) 。
sb.had hardly(=scarcely) done sth.when...=Hardly / Scarcely had sb.done sth.when...
①I had hardly /scarcely closed my eyes when someone knocked at the door.=Hardly / Scarcely had I closed my eyes when someone knocked at the door.我刚一闭上眼,就有人在敲门了 。
【when后面加什么时态,when后面接的哪个时态的从句?】②I had hardly /scarcely entered my room when the telephone rang.=Hardly /Scarcely had I entered my room when the telephone rang.我刚一走进房门,电话就响了 。

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