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初中时间状语从句专项复习基础知识点（一）w h e n,w h i l e和a s引导时间状语从句的用法一、w h e n的用法如果只从现象来看，w h e n从句用的最多的是一般过去时，而主句的时态没有限制,根据具体情况而定。
1.W h e n h e w a s a c h i l d h e w a s a l w a y s t r y i n g o u t n e wi d e a s.他小时候就常常试验一些新的设想。
2.W h e n s h e c a m e i n t o m y r o o m,I w a s j u s t r e a d i n g a b o o k.她走进我房间时，我正在看书。
3.W e r e y o u w r i t i n g w h e nt h e t e a c h e r c a m e i n?老师进来的时候，你在写信吗？4.S o r r y,I w a s o u t w h e ny o u c a l l e d m e.对不起，你打电话来的时候我出去了。
5.H e w a s o n t h e p o i n t o f l e a v i n g w h e n s o m e o n e k n o c k e d a t t h e d o o r.他正要走，这时有人敲门。
6.I t h o u g h t o f i t j u s t w h e n y o u o p e n e d y o u r m o u t h.就在你要说话的时候，我也想到了。
7.I h a d h a r d l y[s c a r c e l y]c l o s e d m y e y e s w h e ns o m e o n e k n o c k e d a t t h e d o o r.我刚一闭上眼，就有人在敲门了。
根据以上的例句，我们可以总结出一点：w h e n从句的A事件，相当于另一个事件B发生的时间点。
【初中英语】状语从句知识点(大全)含答案解析一、初中英语状语从句1．Our parents always give us many useful suggestions, however, we sometimes can’t understand them ________ we get into trouble.A．if B．when C．though D．until【答案】D【解析】【详解】句意“我们的父母会给我们许多有用的建议，然而有时直到我们陷入麻烦才能理解他们”。
A.如果，引导条件状语从句；B.当……时候（引导时间状语从句）；C.尽管（引导让步状语从句）；D.直到（引导时间状语从句）。
根据句意可知，表示“直到我们陷入麻烦才能理解他们”，not...until...直到……才……，故选D。
2．I won't go he comes back.A．until B．while C．when D．why【答案】A【解析】句意：直到他回来，我才走。
A. until 直到； B. while当---时候； C. when当---时候； D. why为什么；not---until--- 直到---才---；故选A3．— Is everyone here today?— No, Lucy is at home ________ she has got a high fever.A．because B．if C．until D．unless【答案】A【解析】【详解】句意：——今天大家都到齐了吗？——没有，露西因为发高烧呆在家里了。
A. because因为；B. if如果；C. until直到……才；D. unless除非，如果不。
露西呆在家里没有来是因为发高烧的原因。
故答案为A。
4．I enjoy fresh air so always sleep with the window open ______ it is really cold．A．unless B．when C．if D．Since【答案】A【解析】【分析】【详解】句意：我喜欢新鲜空气，因此我总是让窗户开着，除非真的很冷。
以when 引导的时间状语从句- When I got home, my son had finished his homework. (主句动作发生在从句之前)- When(当...时候, 主语+did) we arrived, it was raining.- When(正当...时候，主语+be+doing) I was playing the computer games, my mum came in. - He is always nervous when he speaks to strangers.- I usually walk to school when it rains.以while 引导的时间状语从句- While I was reading, my brother was playing with his toy cars. (主从句子动作同时发生)- While/When/As he was studying in the library, I saw him. (表示一段时间时，while/when/as 可替换)while引导的从句的谓语动词必须是持续性动作:I saw him while(x) I was getting off the bus.(x)I saw him when/as I was getting off the bus.以as 引导的时间状语从句- He will grow wiser as he grows older. 随着年龄的增长，他会聪明起来。
（随着，表示时间的推移，这时，不用when/while）- He entered the room as/when/while the meeting was going on. 正当开会的时候，他走进房间。
以before引导的时间状语从句- He had washed his hands before he had dinner. (主句动作先于从句动作)- Please clean the house before you move in.以after 引导的时间状语从句- She went on holiday after she had taken the examination. (从句动作先于主句)- You can watch TV after you finish your homework.以since 引导的时间状语从句- She has been in the house since she came to the city. (主句完成时态，从句过去时)- I have taught them English since last year.以as soon as引导的时间状语从句- I will write to you as soon as I get to America. 我一到美国就会给你写信。
状语从句1. 时间状语从句2. 条件状语从句3. 原因状语从句4. 结果状语从句5. 比较状语从句6. 目的状语从句7. 让步状语从句8. 地点状语从句用来修饰主句中的动词，副词和形容词的从句叫状语从句。
根据其含义状语从句可分为时间状语从句，地点状语从句，条件状语从句，原因状语从句，结果状语从句，比较状语从句，目的状语从句，让步状语从句。
1. 时间状语从句(1)时间状语从句常用when, as, while, before, after, since, till, until, as soon as等连词来引导。
例如：It was raining hard when got to school yesterday.While he was doing his homework, the telephone rang.As he walked along the lake, he sang happily.He had learned a little Chinese before he came to China.After he finished middle school, he went to work in a factory.(2)在时间状语从句里，通常不用将来时态，用现在时态表示将来的动作或状态。
例如：I’ll ring you up as soon as I get to New York.I will tell him everything when he comes back.He won’t believe it until he sees it with his own eyes.(3)在带有till或until引导的时间状语从句的主从复合句里，如果主句用肯定式，其含义是“一直到……时”，谓语动词只能用延续性动词。
如果主句用否定式，其含义是“直到……才……”, “在……以前不……”, 谓语动词可用瞬间动词。
状语从句一、知识框架二、知识梳理（一）定义在复合句中修饰主句中的动词、形容词和副词的从句叫状语从句。
状语从句根据它表达的意思不同可分为时间状语从句、地点状语从句、条件状语从句、比较状语从句、目的状语从句、结果状语从句、方式状语从句、让步状语从句和原因状语从句等。
状语从句如果放在主句前通常用逗号分开，放在主句之后一般不用逗号。
（二）九类状语从句一）时间状语从句1、从属连词分类1）基本类包括when, while, as, whenever, before, after, since, till, until, once (一旦), as soon as等。
Did anyone call when I was out?We have known each other since we were children.You’ll feel better after you take the pills.Make sure that all the lights are off before you go to bed.2）名词类包括the moment, the minute, the second, the instant, every time, each time, (the) next time, the last time, any time, the first time等。
Tell me the moment (that) you get the results.Next time you come in, please close the door.He felt nervous each time she spoke to him.The last time we talked he said he needed another two days.3）副词类如immediately, directly, instantly, presently等。
状语从句讲解及习题附答案（一）状语从句概述定义状语从句用作状语，是起副词作用的句子。
位置状语从句可以放在主句之前，也可以放在主句之后，时间、条件、原因和让步状语从句放在句首时需要用逗号和主句隔开。
分类根据其作用可以分为时间、地点、原因、条件、目的、让步、方式和比较等状语从句。
作用它可以修饰谓语、非谓语动词、定语、状语和整个句子。
（二）状语从句详解1. 时间状语从句引导词用法示例when 意为“当…的时候”。
When引导从句的谓语动词可以是延续性动词，也可以是瞬间动词。
并且when有时表示“就在那时”A liar is not believed when he speaks the truth.说谎者讲真话时也没有人相信。
When he arrives, I’ll call you. When you laugh and smile, your body relaxes.while 意为“在…的时候，在…的同时”。
While引导从句的谓语动词必须是延续性的，发生时间较长，并强调主句和从句的动作同时发生（或者相对应）。
While有时还可以表示对比。
While I was standing at the window, I saw several boys running along the street.While John was watching TV, his wife was cooking.as 意为“一边…一边…”。
As引导的动作是延续性的，发生时间较短，一般用于主句和从句动作同时发生；as也可以强调一前一后。
The writer was angry as he was travelling on a train to London because someone had invaded his “space”.He smiled as he stood up.after 意为“在…之后”。
状语从句1.在主从复合句中修饰主句中的动词，形容词，副词等的从句叫状语从句。
可分为，时间状语从句，地点状语从句，原因，目的，结果，条件，让步，比较和方式状语从句。
2.时间状语从句起时间状语作用的句子；可放在句首，句中和句尾常用引导词：when，while, as, after, before, since, till, until, the moment, hardly ⋯when , no sooner ⋯than when, while, as 的用法1)when 用法最广，常可代替while 和as, 在while 引导的从句中，动词只能是延续性的When the fire broke out, all the students were sleeping soundly.The telephone rang while I was taking a bath.2)当两个表示时间延续的动作同时发生而又有对比意味的时候，用while ，在这样的复合句中，主句从句的时态通常是相同的。
Father was preparing a report while I was playing PC games.3)常用as 的情况：一边⋯一边；表示随着短暂动作的发生，另一行为伴随发生As he talked on, he got more and more excited.until 和till 的用法表示“一直到⋯”时，主句和从句都用肯定式；I will wait until/ till the concert is over. 表示“直到⋯才⋯”是，主句用否定，从句用肯定式。
They can't go untilSunday.since 的用法since 引导的从句中，如果是持续性动词，往往理解为某一状态的终止。
He has written to me frequently since he was ill. 自从他病好以来，他常写信给我。
状语从句副词性从句（状语从句）（一）时间状语从句：用一般现在时表将来1．When（当……时）引导●从句用一般现在时/现在完成时：when + S.+ do/have done……例：I will let you know when you come.●When it comes to +名词/动名词，表示“当涉及（谈）到…..”例：Doing your homework is a sure way to improve your test scores, and this is especially true when it comes to classroom tests.●若从句用一般过去时，主句用过去进行时/be about to（打算）结构，说明主句用来表示从句发生的背景，when就表示为“正在这时”例：I felt somewhat disappointed and was about to leave, when something occurred which attracted my attention.2．While（当……时）引导●从句用一般现在时/现在完成时：while + S.+ do/have done……3．As（正当……时，一边…..一边）引导4．Whenever（无论何时）引导5．Since（自从……以来）引导●主句过去完成时+ 从句一般过去时：S. + did…since S.+ had done●常见用法：It is + time + since……，表示“自从……以来有（一段）时间”例：It is two years since I last met her.6．Every/each time（每当）引导7．Before（在……之前、趁着……还没有、还没来得及）引导●若从句需要用情态动词的，只能用can/could例：Please tell me the truth before I can guess it.●常见用法：It is/was/will be + time +before……，表示“过一段时间（才）会……”例：“It is a long time since I saw you last.”“Yes. And it will be a time before we see each other again.”8．After（在……之后）引导9．Till/until（直到）引导●一般结构：not…（短暂v）...until……，表示“直到……才….”倒装结构：Not until…….，后面倒装强调结构：It is not until……that……例：They did not stop discussing until they came to a conclusion.= It was not until they came to a conclusion that they stopped discussion.= Not until they came to a conclusion, did they stop discussion.10．As soon as（刚……就）引导例：Come here as soon as you finished the work.11．The moment/minute/instant（刚……就）引导例：I recognized her the moment I saw her.12．Hardly/scarcely/(only)just……when（刚……就）引导●从句一般过去时+ 主句过去完成时：S. + had hardly/scarcely/(only)just done…,when S.+ did●若hardly/scarcely/(only)just置于句首，主句须倒装（had+ S.+ done）例：He had hardly left school when it began to rain.=Hardly had he left school when it began to rain.13．No sooner……than（刚……就）引导●从句一般过去时+ 主句过去完成时：S. + had no sooner done…, than S.+ did●若no sooner置于句首，主句须倒装（had+ S.+ done）例：We had no sooner reached the top of hill than we all sat down to rest.=No sooner had we reached the top of hill than we all sat down to rest.（二）地点状语从句1．Where（在……地方）引导：从句用一般现在时例：Where there is smoke, there is fire.2．Wherever（无论在哪里）引导例：Wherever he may be, he will be welcome.（三）条件状语从句：用一般现在时表将来1．If（如果、假如）引导：用虚拟语气●if引导得从句中，若有were, had, should三词，可以省略if，并且倒装（谓语置前）例：If I had known about it, I would have told you.= Had I known about it, I would have told you.●If从句+主句= 祈使句/省略句+ and +…….例：If you give me some food, I won’t die of starvation（饥饿）.= Some food and I won’t die of starvation;2．Suppose/supposing（假设）引导例：Suppose we cannot get the necessary equipment（设备）, what shall we do? 3．Unless（除非、如果不）引导●Unless从句+主句= 祈使句/省略句+ or +…….例：Unless you give me another drink, I will die of thirst.= Another drink or I will die of thirst.4．As/so long as（只要）引导例：We can surely overcome these difficulties so long as we are closely united.5．If only/only if（只要）引导例：We can surely get gains, if only we work hard.6．In case/lest（万一）例：You should take good care of your kid, in case they are ill.7．Provided/Providing/Given that（假如）引导例：We will let you use the room provided that you keep it clean and tidy.8．On condition that（假如）引导（四）原因状语从句1．Because（因为）引导●表示“直接、唯一的原因”，通常放在句后，可以与not, but, only连用例：He was angry not because we were late but because we made a noise.2．As（因为）引导●表示“显而易见或大家都知道的原因”，语气较弱例：Everyone likes you as you are both kind and honest.3．Since（因为、既然）引导●表示“间接或附带的原因”，通常放在句首例：Since she insists, you must come.4．Now/seeing that（既然）引导例：Now/Seeing that you are all here, let’s try and reach a decision.5．Considering that （考虑到）引导例：Considering that he began learning English only a year ago, he speaks very well. 6．In that（由于、因为）引导例：He was late in that he didn’t catch the first bus.（五）让步状语从句1．Though/although/as（虽然）引导●Though/although…..yet连用，表示“虽然…..但是……”例：Though/although we cannot see air, (yet) it exists everyone.●as引导得从句置于句首，且倒装（表语、状语、动词置于as前）表语倒装：可以省略冠词例：Tried as I was, I stayed up late studying last night.Children as he is, he knows a lot of English.状语倒装：Fast as he read, you can’t finish novel in three days.谓语动词倒装：Try as he would, he couldn’t lift the rock.2．Even if/though（即使）引导例：Nobody lost his patience as though the meeting was long and boring. 3．However/no matter how（无论如何/怎样）引导例：We’ll continue to work, no matter how/however hot it is.4．Whatever/no matter what（无论什么）引导例：Whatever/no matter what r you may do, do your best.5．Whoever/no matter who（无论谁）引导例：Whoever/no matter who all cannot break the rules, we must keep the law. 6．Whether……or/no matter whether…..or….（不管……还是）引导例：Whether/no matter whether you can do or cannot do, you must try it. 7．Whether or not/whether……or not（不管是否……）引导例：Whether or not we had a baby, we couldn’t survive only on my salary.= Whether we had a baby or not, we couldn’t survive only my salary.（六）方式状语从句1．As（如，按照）引导例：When in Roma do as the Romans do.2．Just as（正如）引导例：Most plants need air just as they need water.3．As if/though（好像，仿佛）引导●引导的从句常用虚拟语气，除了叙述的情况实现的可能性较大例：He speaks English as if/though he were an Englishman.例：It looks as if/though the coming autumn harvest will be even better than the last one. （七）目的状语从句1．So that（以便、为了）引导●从句中谓语部分可以用can/could，may/might例：I will give you my phone number, so that you can call me when you arrive here. 2．In order to（以便、为了）引导●从句中谓语部分只能用may/might例：We should do our utmost最大可能in order that we may be able to overfulfil 超额完成the task.3．For fear that/lest（以免、以防）引导●从句用虚拟语气“should +V.”例：Batteries 电池must be kept in dry place for fear that/lest electricity should leak 渗漏away.4．In case（以免、以防）引导●从句中谓语部分不用虚拟语气例：Better take more clothes in case the weather is cold.（八）结果状语从1．that（因而）引导例：What’s the matter that they still haven’t answered our e-mail?2．so that（因而）引导●主句，+ so that，且从句中谓语部分只能用may/might例：The temperature is increased , so that the volume of the gas can become greater. 3．So…..that（如此……以至）引导●so +形容词/副词+a/an+名词+ that例：It is so hot a day that we cannot sleep.●so置于句首时，需倒装状语例：So fast did he run that I could not keep up with him●so + much/little/few/many + that，而不用such…..that例：She has so little education that she is unable to get a job.4．Such…..that（如此……以至）引导●Such +名词（可数的单数名词）+ that例：It is such a lovely day that everybody is feeling happy and gay.（九）比较状语从句1．Than（比……）引导例：There are more vocabularies in this unit than in that one.2．As……as（如……一样）引导●As +形容词/副词+a/an+名词+ as + 省略句例：He is as clever a boy as his brother.例：This book is nearly as thick as that one(is).3．Not so……as（不如……一样）引导●As +形容词/副词+a/an+名词+ as + 省略句例：You are not as tall as she.4．The+比较级，the+比较级（越……越…….）引导例：The hotter that air becomes, the lighter it gets.例题1、（）______ your daughter has not come back , let me take you to the Friendship Hospital.A WhenB SinceC ThatD For2、（）______ Tom is not feeling well today , he has to stay at home.A ThoughB ForC FindingD As3、（）They are ______ hard-working students that they have already made ______ much progress since thay came here.A so ; soB such ; suchC so ; suchD such ; so4、（）______ we have finished the book we shall start doing some exercises.A For nowB Since nowC Now thatD Since now5、（）He asked us not to be noisy ______ we should wake the baby.A in cseB in the caseC in case ofD in this case巩固练习1、（）______ you are familiar with the auther`s ideas , by reading all the sections as quickly as you can.A Ever sinceB As long asC So thatD Now that2、（）The boy has to learn ______ things that he hardly has time for play.A so manyB such manyC so fewD such few3、（）In the old days the poor worker worked long hours every day ______ he could support his whole family.A becauseB thoughC unlessD so that4、（）Tell him that I will call him back , ______ he gives me a call.A in most casesB in caseC in any caseD in case of5、（）______ you have reminded me , I will try to be a teacher.A Now thenB So thatC Now thatD In order that6、（）You will have to study for many years ______ you may become a brain surgeon.A in order thatB in thatC althoughD soKey 1~5 BDDCA 1~6 DADBCA二、习题1、（）It is almost impossible to become skilful in speaking a language ______ you use it constantly.A but forB if onlyC exceptD unless2、（）Everything will be all right ______ Tom is left to do the work in his own way.A as far asB mean whileC so long asD in case3、（）Do remind me of the date again tomorrow ______ I forget.A in caseB except thatC even ifD as though4、（）You must do the experiment ______ the teacher told you.A asB sinceC so thatD unless5、（）I could not resist having another piece of cake even ______ I was supposed to lose weight.A althoughB howeverC otherwiseD though6、（）______ I suggest , he always disagree.A WhatB HowC WhateverD How a7、（）However ______ you hate them , you must work with them.A very muchB too muchC much tooD much8、（）Try ______ he might , Tom could not get out of the trouble.A as ifB altoughC ifD as9、（）______ whales are very large , they are no longer an even match for man.A SinceB BecauseC Now thatD Although10、（）Man must have food just ______ plants must have sunlight.A forB likeC becauseD as巩固练习1、（）______ I know , the visitors are all satisfied with the arrangement in the next few days.A As far asB As long asC As well asD As soon as2、（）______ convincing an argument is , it needs support of evidence.A No matterB ThoughC HoweverD As3、（）Anyone can borrow books from the library ______ he has a library card.A so long asB sinceC even thoughD unless4、（）______ much advice I gave him , he did exactly what he wanted to do.A HowB WhateverC WhatD No matter how5、（）Remember , science requires your whole life ______ you had two lives to give , they would not be enough.A AlthoughB ThoughC If onlyD Even if6、（）I am sure that Laura`s latest play , ______ staged , will prove a great success.A sinceB unlessC onceD until7、（）Send us a message , ______ you have any difficulty.A in case thatB in caseC whileD as8、（）Electricity flows through a wire ______ water flows through a pipe.A whileB just asC much asD whenever9、（）Food shortage will long be a world problem ______ much has been done to supply enough for everyone.A althoughB evenC no matterD since10、（）I do not like the city , ______ though I have been living here for more than ten years.A evenB asC everD butkey1~5 DCAAD 6~10 CDDDD 1~5 ACADD 6~10 CBBAA。
状语从句（adverbial clause）复习要点：掌握句法功能，记住连接词语法意义：状语从句是复合句中的一种，整个从句作主句的状语，修饰主句中的谓语动词、形容词、或副词。
置于句首时，状语从句后面一般要有逗号隔开；如果状语从句置于句尾，则从句一般不用逗号。
按照所作的状语和意义可分为时间、地点、原因、目的、结果、条件、让步、方式和比较等九种状语从句。
具体如下：一、时间状语从句（Adverbial Clauses of Time）时间状语从句通常由when,whenever,as,while,before,after,assoon as,since,once,no sooner...then,hardly/scarcely...when,tiLl/until 以及the moment,directly,immediately,the second,thefirst time,next time,every time,等引导。
1.由when,as,while 引导的状语从句：1）when 引导时间状语从句，表示当···，其谓语动词可以是延续性的，也可以是非延续性的，其作用最广泛。
When spring comes,trees turn green,When it rains,I usually go to work by taxi.When we were having lunch,the light went out.I will ring you up when I return.When she pressed the button,the lift stopped.He was eating his breakfast when the doorbell rang.be about to do...when...“就在那/这时，（突然）另一个动作发生了，在这儿只能用when。
状语从句练习题基础、提高、难题_汇总(含答案)一、初中英语状语从句1．Square Dancing is good exercise for the old, sometimes it makes a lot of noise.A．IfB．AlthoughC．UntilD．Because【答案】B【解析】【详解】句意：虽然广场舞对老年人来说是很好的运动，但有时也会制造很大的噪音。
A. If连词，如果，引导条件状语从句；B. Although连词，虽然、即使，引导让步状语从句；C. Until连词，直到，引导时间状语从句。
D. Because连词，因为，引导原因状语从句。
根据前后文之间的“让步”关系可知，选用although。
故选：B。
2．I will go to the English club tomorrow I am too busy.A．since B．if C．unless D．until【答案】C【解析】【详解】句意：明天我将会去英语俱乐部，除非我太忙。
since自从；if如果；unless除非，如果不；until直到…时候。
根据句意可知，这里表示的意思是“如果我不忙，我会…”，故应选C。
3．— When did you go to bed last night?— ____________ I finished my homework.A．Until B．Not until C．When D．While【答案】B【解析】not …until 表示直到…才，与短暂性动词连用，故选B4．It is necessary for children to exchange ideas with parents from time to time ________ a good parent-children relationship could be set up.A．so that B．because C．as soon as【答案】A【解析】【详解】句意“为了建立良好的亲子关系，孩子们有必要不时地与父母交流思想”。
状语从句知识点总结经典1一、初中英语状语从句1．--- What was the party like?--- Wonderful. It’s years ____ I enjoyed myself so much.A．since B．after C．when D．before【答案】A【解析】试题分析：句意：聚会怎么样？太精彩了，好多年了我没玩的这么高兴过。
此题是考查句型：It’ s years + since + 一般过去式，此题中的动词是enjoyed延续性动词，应从动作结束算起，可以翻译成它的反义词，故选A。
考点：考查连词的用法2．You won't succeed _____ you work hardA．if B．because C．unless D．so that【答案】C【解析】【详解】句意：你不会成功的，除非你努力工作。
if如果；because 因为，引导原因状语从句；unless如果不，除非；so that以至于，引导结果状语从句；为的是，引导目的状语从句。
根据句意可知，这里表示“如果不努力工作”，故应选C。
3．There are fewer and fewer tigers in India. The situation will continue _______ humans stop hunting them for their fur and bones.A．if B．unless C．because D．since【答案】B【解析】试题分析：句意：印度有越来越少的老虎。
如果人类不停止为了虎皮和虎骨猎杀老虎，情况会继续。
A.if如果，表示条件；B.unless如果不，表示相反的条件；C.because因为，表示原因；D.since自从，表示时间的起点；既然，表示原因。
“如果不”停止，情况会继续。
故选B。
考点：考查连词的用法4．Our teachers have been with us for nearly three years we came to junior high school. We should thank them for what they have done for us.A．until B．before C．since D．while【答案】C【解析】句意：自从我们来到初中，我们的老师们已经和我们在一起将近三年了，我们应该感谢他们为我们所做的一切。
状语从句状语从句在句中作状语，可分为：时间、条件、让步、原因、目的、结果、比较、地点、方式状语从句。
一、时间状语从句引导时间状语从句的连词有：when, as, while, until, not…until, before, after, since, the minute, the moment, each( every, next, the first) time等。
时间状语从句中一般用一般现在时或一般过去时。
1．When , while, as都可解释为“当```的时候”但侧重点有所不同。
1)WhenEg: When I arrived home , I had a little rest.注意点：when 从句的主语与主句主语相同，谓语动词是be 动词时，从句主语和be可以省略。
Eg: When (she was) walking along the street, she met her class teacher.2)AsAs 除了表示“当```的时候”，还可表示为“一面```一面”，“随着”Eg: He sang as he danced.(一面```一面)You will grow wiser as you grow older.(随着)3)While表示“当```的时候”强调主句的动作和从句的动作同时发生，从句一般用进行时，从句动词必须是延续性动词。
Eg: While we were working, they were having a rest.While (they were) having a discussion, they got very confused.注意点：while 有对比的含义，解释为“然而”。
eg: I prefer black tee, while he likes coffee.2．until, not…until表示“直到```才”,在肯定句中主句常用延续性动词；在否定句中主句常用短暂性动词。
