1、概念概念概念概念:在复合句中，由时间在复合句中，由时间来年借此引导的状语从句来年借此引导的状语从句叫做时间状语从句。（再叫做时间状语从句。（再复合句中，要主义主句和复合句中，要主义主句和从句的时态大多都要保持从句的时态大多都要保持一致。一致。When/whileWhen/while的区别的区别 When表示 主从句两个动作同时发生或先后发生。而while表示主从句两个动作同时发生或强调主句的动作在从句动作期间发生。(1）_ they are waiting for the New Year,they listen to music,sing songs and dance.(2)_the bo
2、y saw his mother,he stopped crying.WhileWhen1 12 23 34 4when+短暂性动词或延续性动词while+延续性动词（一般为be doing）（1）He was doing his homework _ I saw him.(2)Please dont talk so loud_ others are working.进行时+while+进行时She was dancing _I was singing.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都可以使用。_she was singing,we all l
3、ost ourselves in her beautiful voice.When/whileWhen/while的区别的区别延续性动词表达的动作能够延续，如：keep保存、维持，walk走路，read阅读等。非延续性动词也称瞬间动词，所表达的动作不能够延续。如，hear听到，return归还，see看见。whenwhilewhileWhen/While/AsWhen When 常用于以下句式常用于以下句式：be doing/be going to do sth.be about to do sth Had just donewhen正在/刚要/刚做完（突然）AsAs的用法的用法 As the
4、 time went on，the weather got worse（as表示“随着”之意）The atmosphere gets thinner and thinner as the height increases随着高度的增加，大气越来越稀薄。As 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。The little girls sang as they went小姑娘们一边走，一边唱。The sad mother sat on the roadside，shouting as she was
5、crying伤心的妈妈坐在路边，边哭边叫。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。与while从句的不同是，as从句一般不用现在进行时，用一般过去式。易混引导词易混引导词untiluntil及其否定的区别：及其否定的区别：在until（意为“直到”）引导的从句中主句应用延续性动词，表示主句的动作一直延续到从句的时间或动作为止。在notuntil(意为“直到时”)引导的从句中主句可用瞬间性的动词，表示主句的动作在从句的时间或动作发生时才开始。1）It may last until Frid
6、ay.这可能要延续到星期五。2)Dont open it until your birthday.等到你过生日那天再打开。1.I have returned home four times since I came here.2.She has been working here(ever since)he left school.sincesince的用法的用法常用句型：It has been(is)+时间段+since从句“自从有多长时间了”It has been(is)six years _ she graduated from the university.sincebeforebef
7、ore的用法的用法：before 所引导的时间状语从句 所表示的动作 发生在主句动作之后。如果强调主句的动作发生在前，主句谓语 要用过去完成时。before 引导的从句用一般过去时，如不强调动作的先后，主句和从句均用一般过去时。before当主句用将来时，从句总是用现在时She worked in shanghai before she came here.she had studied English for six years before she went to college.It will be four days before they come back.BeforeBefore
8、的用法的用法124We had sailed four days and four nights before we saw land.才Please write it down before you forget it.趁（还还未）Before I could get in a word,he had measured me.还还没来得及beforebefore的用法的用法3We hadnt run a mile before he felt tired.还还没有/不到就含有含有beforebefore的句型结构的句型结构1.It will be/was+一段时间+before”过多久才”I
9、t_(还要过两年）he leaves the country.2.It will be/was+not+一段时间+before“不多久就”It was _(不久)before he left the country.will be two years beforenot youngafterafter的用法的用法：after所引导的时间状语从句 所表示的动作 发生在主句动作之前 如果强调从句的动作发生在前 从句谓语 要用过去完成时 主句用一般过去时。如不强调动作的先后 主句和从句 均用一般过去时.如 After he did his homework,he went to bed.After
10、she had waited for him for an hour,she started for home.主句是 一般将来时 after 从句用 一般现在时或现在完成时 代替将来完成时如 I ll write to you after I finish/have finished my work.主将从现原则主将从现原则一、时间状语从句的主句是一般将来时，那么从句常常用一般现在时。如:When I grow up,Ill be a nurse and look after patients.我长大后要当一名护士，照顾病人。二、如果主句是祈使句，那么从句通常要用一般现在时。如:Dont l
11、augh at me when I make a mistake.我犯错误的时候不要笑话我。三、如果主句是含有情态动词的一般现在时，根据需要从句多用一般现在时。如:You should be quiet when you are in the reading room.在时间状语从句里，主句用一般将来时，从句用一般现在时表示将来的动作或状态。其他连词其他连词添加标题添加标题Each time,every time,the first time,by the timeEach time he came to my city,he would call on me.The first time I
12、 came to Shanghai,I loved it very much.By the time the doctor arrived,the man had come to.The moment,the minute,the second一就hardly/scarcelywhen，no sooner than 表示“一就”We had hardly got into the country when it began to rain.Once,as soon as,directly,immediatelyAs soon as I have finished it,Ill give you
13、 a call.Once you show any fear,he will attack you.He made for the door directly he heard the knock.练习练习：Choose theChoose the answer.answer.1.It was quiet _those big trucks started coming through the town.A.When B.after C.until D.unless2.It seemed only seconds _the boy finished washing his face.3_you begin,I think you must continue.A.When B.whenever C Once D.Even if4.I recognized you _I saw you at the airport.A.The moment B.while C.after D.onceCBCATHANK YOU演讲人：优品PPT 演讲时间：20XX
