《时间状语从句》PPT课件

时间状语从句 引导时间状语从句的普通类从属连词有when（当时），while（在期间），as（当，一边一边），before（在之前），after（在之后），since（从以来），till/until（直到），whenever（无论何时），as soon as（一就）等。时间状语从句eg.1.When I went into the classroom,he was reading.当我走进教室时，他正在看书。2.We must strike while the iron is hot.我们必须趁热打铁。3.He read a newspaper as he went along.他边走边看报纸。4.I will tell you after they leave.于他们走后我再告诉你。5.I told him to come back whenever he wants to.我告诉他什么时候想回来就回来。6.I waited till/until she was back.我一直等到她回来 时间状语从句when,whilewhen,while,as表示主句谓语作和从句的谓语动作同时发生或几乎同时发生。when表示点时间时，从句中用短暂性动词；表示段时间时，用持续性动词eg.When I got home,my family were already having dinner.我到家的时候，全家已在吃晚饭。（when表示点时间）When they were still talking and laughing,the teacher came in.当他们还在说笑的时候，老师进来了。（when表示段时间）He waved a hello when he saw her.当他看见她的时候，就挥手打了个招呼。（when表示点时间）When you think you know nothing,you begin to know something.当你认为自己一无所知的时候，就开始知道一些事情了。（when表示一段时间）时间状语从句 When1.当when意思是正当时候（即 at that moment）时，when只能跟在前一分句之后。eg.He was about to go to bed when the doorbell rang.他正要上床，忽然门铃响了。They were watching the World Cup when suddenly the lights went out.他们正看着世界杯比赛，突然灯灭了。They had just arrived home when it began to rain.他们刚到家，天就开始下雨了。2.有时when表示虽然，尽管的含义，相当于although或since。eg.He walks when he might take a taxi.尽管可以打的，但他还是步行。How can you hope for mercy yourself when you show none 既然你不宽恕别人，你自己又怎能希望得到别人的宽恕呢？时间状语从句 whilev while通常表示一段时间，从句中宜用持续性动词作谓语。eg.Strike while the iron is hot.v 趁热打铁。v She fell asleep while she was reading the newspaper.v 她在看报的时候睡着了。v while有时可以作并列连词，表示对比，可译成而。v I am fond of English while he likes maths.v 我喜欢英语而他却喜欢数学。v We slept while the captain kept watch.v 我们睡觉而上尉担任警戒。v while有时可引导让步状语从句，意思是虽然。v While they love te children,they are strict with them.v 虽然他们都爱他们的孩子，但却对他们要求严格。vATTENTION:虽然during 与 while 意思很相近，但是during是介词，不能引导从句。时间状语从句 as as表示点时间时，从句中用短暂性动词；表示段时间时，用持续性动词。as和when两者经常可以通用。eg.The thief was caught as when he was stealing in the supermarket.小偷在超市行窃时被逮住了。I saw Jim as when he left the meeting room.吉姆离开会议室时候我看到了他。as表示 一边一边，强调从句和主句中两个动作交替进行或同步进行。eg.They talked as they walked.他们边走边聊。He looked behind from time to time as he went.他一边走，一边不时地往后看。as表示随着 eg.As time goes on,its getting warmer and warmer.随着时间的推移，天气变得越来越暖了。时间状语从句when,while,as的用法区别 只有当从句表示的是段时间，即其谓语动词有持续性特征时，这三者可以通用互换。eg.I got the news on the radio when while as I was having breakfast.我在吃早饭的时候从收音机里获悉这一消息。在下列情况下，三者彼此之间不能替换使用：aas更强调同一时间或紧接的一前一后或伴随着的变化。eg.We listened to the singer sing as he played the guitar.我们听着歌星边弹吉它边演唱。I thought of it just as you opened your mouth.你一张嘴我就知道你要说什幺 As he grew older,he became less and less active.随着他年龄的增长，他变得越来越不活泼了。时间状语从句 bwhen更强调特定时间，还可表示从句中的动作先于或后于主句的动作。eg.When I had given Mary the spare ticket,I found my own already gone.当我把多余的票给了玛丽时，我才发现我自己的票已不知去向。（从句动作发生在主句之前，注意主从句的时态）When I finally got there,he meeting had been on for ten minutes.当我最终赶到那里时，会议已开始十分钟了。（从句动作发生在主句之后，注意时态）时间状语从句cwhile从句只能表示延续的动作或状态或主从句中动作的对比。eg.She thought I was talking about her daughter,while in fact,I was talking about my daughter.她以为我在谈论她女儿，而事实上，我在谈论我的女儿。时间状语从句 d若表示两个短促动作几乎同时发生时，用 as场合多于when。eg.As he finished his speech,the audience burst into applause.他结束演讲时，观众爆发出雷鸣般的掌声。时间状语从句 before before表示在一段时间之前。eg.I must finish all the work before go home.回家之前我必须干完所有的活。You must first learn to walk before you try to run.在想要跑以前，你得先学会走。He had learned English for three years before he went to London.他去伦敦之前已学了三年英语。before 从句往往带有否定的含义。eg.He ran off before I could stop him.我还没来得及阻止他，他就跑掉了。Take it down before you forget it.趁着还没忘记的时候就记录下来。时间状语从句after after表示在一段时间之后。eg.Lets play football after school.放学后我们踢足球吧。The sun came out soon after the storm stopped.暴风雨过后不久，太阳出来了。时间状语从句Since since表示自以来。表示动作从过去某一点时间一直延续到说话时间为止。主句中通常为延续性动词的现在完成时，since从句中一般用短暂性动词的一般过去时。eg.It has been just a week since we arrived here.我们到这儿刚刚一星期。Where have you been since I last saw you?自上次我见过你之后，你去了哪里？Since she was young,she has been collecting stamps.她自年轻时起就一直集邮至今。时间状语从句till,until 1Until/till用于肯定句时，表示直到为止，主句必须为持续性动词。eg.We shall wait until/till he comes back.我们将一直等到他回来。Everything went well until/till that accident happened.直到发生那意外之前，一切都正常。2 notuntil/till表示直到才，主句通常要用短暂动词，这时until和till可用 before代替。eg.I didnt leave until/till before she came back.直到她回来，我才离开的。People do not know the value of their health till until before they lose it 人们直至失去了健康才知其可贵。3当not until位于句首时，主句中的主语、谓语要使用倒装语序。eg.Not until she stopped crying did I leave.直到她不哭了，我才离开的。v 4.在强调句型中一般只用until,不用till 1.eg.It was not until she took off her dark glasses that I recognized her.时间状语从句whenever whenever是when的强势语，它描述的不是一次性动作，而是经常发生的习惯性动作。eg.You are always welcome whenever you come.无论你何时来都欢迎。Whenever we met with difficulties,they came to help us.每当我们遇上困难的时候，他们就来帮我们。时间状语从句as soon as as soon as.可译为一就，用来表示主从句的动作是紧接着发生的。eg.He will come and see you as soon as he can.他一有空就来看你。He rushed home as soon as he got the good news.他一得到这个好消息就奔回家。时间状语从句Attention:在时间状语从句中，不能用一般将来时、过去将来时态或将来完成时，而要用相应的一般现在时态、一般过去时或现在完成时来代替。eg.Ill telephone you as soon as I get there.我一到达那里就打电话给你。Dont get off the bus until it has stopped.等车停稳后才下车。If I get up late,I will be late for school.If I dont finish my homework,I wont go to bed.由由if引导的从句叫条件状语从句，引导的从句叫条件状语从句，if意为意为“如果如果”若主句是一般将来时，从句要用一般现在时若主句是一般将来时，从句要用一般现在时。If you join the band,you will be famous.=You will be famous if you join the band.If you feel tired must.