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时间状语从句定义: 用表示时间的连词连接一个句子作状语,这样的主从复合句就是时间状语从句。连接时间状语从句的连接词有:when, before, after, while, as soon as, until, since. 这里要注意一点的是,如果主句是一般将来时,从句只能用一般现在时表示将来意义。时间状语从句由when,while引导的时间状语从句。When you think you know nothing, then you begin to know something.当你以为自己一无所知的时候,你就是在开始知道一些事物了。Strike while the iron is hot. 趁热打铁。You can feel the air moving as your hand pushes through it.当你的手在空气中挥动的时候,你就能感觉到空气在流动。Our headmaster laughed as she spoke. 我们的校长边谈边笑。主要时态:主现从不限;主过从四过;主将从现。when, while和as的区别(1)when引导的从句的谓语动词可以是延续性的动词,可以是瞬时动词。并且when有时表示“就在那时”。例如:When she came in, I stopped eating.她进来时,我停止吃饭。(瞬时动词)When I lived in the countryside, I used to carry some water for him.当我住在农村时,我常常为他担水。(延续性的动词)We were about to leave when he came in.我们就要离开,就在那时他进来了。(2)While引导的从句的谓语动作必须是延续性的,并强调主句和从句的动作同时发生(或者相对应)。并且while有时还可以表示对比。例如:While my wife was reading the newspaper, I was watching TV. (was reading是延续性的动词,was reading和was watching同时发生) 。I like playing football while you like playing basketball.我喜欢踢足球,而你喜欢打篮球。(对比)(3)As表示“一边一边”,as引导的动作是延续性的动作,一般用于主句和从句动作同时发生;as也可以强调“一先一后。例如:We always sing as we walk.我们总是边走边唱。(as表示“一边一边”)As we were going out, it began to snow.当我们出门时,开始下雪了。(as强调句中两个动作紧接着先后发生,而不强调开始下雪的特定时间)由before和after引导的时间状语从句注意:before引导的从句不再用否定式的谓语,并且当before引导的从句位于主句之后,有时译成“就,才”。还要注意主句和从句之间的时间关系。当主句用将来时,从句总是用现在时;如果before引导的主句谓语用的是过去完成时,则从句动词多用一般过去时,这样以便体现动作发生的先后。After表示主句动作发生在从句动作之后。主句和 从句的动作的时间关系正好与before引导的从句相反。例如:It will be four days before they come back. 他们要过四天才能回来。Einstein almost knocked me down before he saw me.爱因斯坦几乎把我撞倒才看到我。My father had left for Canada just before the letter arrived.我父亲恰好在信到之前去加拿大了。They had not been married four months before they were divorced. 他们结婚还不到四个月就离婚了。After you think it over, please let me know what you decide.你仔细考虑过以后,告诉我你是怎样决定的。After we had finished the work, we went home.完成工作之后,我们回家了。(从句用过去完成时,主句用一般过去时)由till或until引导的时间状语从句。till和until一般情况下两者可以互换,但是在强调句型中多用until。并且要注意的是:如果主句中的谓语动词是瞬时动词时,必须用否定形式;如果主句中的谓语动词是延续性动词时,用肯定或否定形式都可以,但表达的意思不同。till不可以用在句首,而until可以放在句首。例如:I didnt go to bed until(till) my father came back.直到我父亲回来我才上床睡觉。It was not until the meeting was over that he began to teach me English.直到散会之后他才开始教我英语。I worked until he came back.我工作到他回来为止。I didnt work until he came back.他回来我这才开始工作。Please wait until I arrived.在我到达之前请等我。由since引导的时间状语从句。since引导的从句的谓语动词可以是延续性的动词,又可以是瞬时动词。一般情况下,从句谓语动词用一般过去时,而主句的谓语动词用现在完成时。但在It is +时间+since从句的句型中,主句多用一般现在时。例如:I have been in Beijing since you left. 自从你离开以来,我一直在北京了。Where have you been since I last saw you? 自上次我和你见面以后,你到哪里去了?It is four years since my sister lived in Beijing. 我妹妹不在北京住有四年了。It is five months since our boss was in Beijing.我们老板离开北京有五个月了。由as soon as, 等引导的时间状语从句。(了解)这些连词都表示“一就”。例如:I will go there directly I have finished my breakfast. 吃完早饭,我立即到那里去。The moment I heard the news, I hastened to the spot.我一听到消息,马上赶到了出事地点。As soon as I reach Canada, I will ring you up. 我一到加拿大,就给你来电话。注意:hardly(scarcely, rarely)when / before, no soonerthan相当于as soon as之意。主句用过去完成时,从句用一般过去时。当hardly, scarcely, rarely和no sooner位于句首时,主句应用倒装语序。例如:He had no sooner arrived home than he was asked to start on another journey. 他刚到家,就被邀请开始另一旅程。No sooner had the sun shown itself above the horizon than he got out of bed to commence work.太阳刚从地平线上升起,他就起床劳动去了。Hardly had I sat down when he stepped in.我刚坐下,他就进来了。He had hardly fallen asleep when he felt a soft touch on his shoulder.这个阿拉伯人刚要入睡就感到肩膀上被轻轻一触。由by the time引导的时间状语从句。注意时态的变化:在一般情况下,如果从句的谓语动词用一般过去时,主句的谓语动词用过去完成时;如果从句的谓语动词用一般现在时,主句的谓语动词用将来完成时。例如:By the time you came back, I had finished this book.到你回来时,我已经写完这本书了。By the time you come here tomorrow, I will have finished this work. 你明天来这儿的时候,我将已经完成此工作了。由each time, every time等引导的时间状语从句。例如:Each time he came to Harbin, he would call on me. 他每次来哈尔滨,总是来看我。Whenever that man says“To tell the truth”, I suspect that hes about to tell a lie.每当那个人说“说实在话”的时候,我猜想他就要说谎了。You grow younger every time I see you. 每次遇到你,见你更年轻了。由as long as和so long as引导的时间状语从句。这两个连词表示“只要“例如:You can go where you like as long as you get back before dark. 你可以随意到哪里去,只要在天黑以前回来就行。I will fight against these conditions as long as there is a breath in my body! 只要我一息尚存,我就要反对这种境况。一、when“当时”,引导时间状语从句时,从句用于表示主句动作发生的特定时间。如:The days get longer when spring comes. = When spring comes, the days get longer.春天到来时,白天变得更长了。二、before“在之前”,引导时间状语从句时,表示主句动作发生在从句动作之前。如:Close the door before you leave the room.离开房间前关上门。三、after“在之后”,引导时间状语从句时,表示主句的动作发生在从句的动作之后。如:I went to school after I finished my breakfast.吃完早饭后我就去上学了。四、as soon as“一就”,引导时间状语从句时,表示主句动作紧接着从句动作发生。如:Ill call you as soon as I get home.我一到家就给你打电话。五、until, till“直到”,引导时间状语从句。当主句谓语动词是延续性动词时,主句常用肯定形式;当主句谓语动词是非延续性动词时,主句要用否定形式,即“notuntil/till”意为“直到才”。如:Ill wait here until/till the rain stops.我将在这里等着,直到雨停。You cant go home until/till you finish your work.直到你完成你的工作,你才能回家。时态的呼应和从句的位置状语从句的两手绝活时态的呼应和从句的位置。请看: 第一点时态呼应一般来讲,复合句都要遵循主、从句时态呼应规律,状语从句也不例外。即主句用现在时,从句也用现在时;主句用过去时,从句也用过去的某种时态。如:Be careful when you cross the road.过马路时要小心。You must see the doctor if you are ill.如果你生病了,你必须去看医生主句是一般过去时,从句也要用一般过去时。如:When he was seven years old, he could swim.当他七岁时就会游泳。She turned off the light before she left the office.她离开办公室前就关了灯。第二点主从句的位置,大多数情况下,从句可以位于主句之前,也可以位于主句之后。不过从句在前时,主从句之间必须用逗号隔开。如:Please tell me when he comes back. = When he comes back, please tell me.这是一般现在,一般过去,现在进行,过去进行,现在完成,过去完成,现在完成进行,一般将来,过去将来时的时间状语:1.Often,usually-动词原型do,does,am,is, are2.yesterday,last Sunday,in the past-动词过去式did,was,were3.now-be+doing4.while,at that time,-was doing,were doing5.since从句,for 2 days,-have done,have been+过去的某个时间点-had done,had been7.与现在完成相似-have been+持续动词ing形式8.一切表示将来的时间状语,in+一段时间-将来要发生的一般性动作,will,shall+原型9.与一般将来时相似-would+原型时间状语一般现在时every, sometimes, at , on Sunday,一般过去时yesterday, last week, an hour ago, the other day, in 1982, just now一般将来时next, tomorrow, in+时间,现在完成时 for, since, so far, ever, never, just, yet, till/until, up to now, in past years, always, recently过去完成时before, by, until, when, after, once, as soon as过去进行时this morning, the whole morning, all day, yesterday, from nine to ten last evening when, while将来进行时soon, tomorrow, this evening, on Sunday, by this time, tomorrow, in two days, tomorrow evening从句语法 时间状语在复合句中,担任状语成分的从句称为状语从句。时间状语从句说明主句动作发生或进行的时间。状语从句由连词引导,其位置通常可以放在句首或句末。放在句首是,常用逗号与主句分开;放在句末时,从句前面往往不加逗号。引导的时间状语从句的主从复合句中,动作发生在先的用过去完成时,在后的用过去时。表示前面的叙述所没有提到过的信息。它总是对所描述的事件予以引人注目的强调,意为“这时;突然”;当位于句末的分句具有引种用法时,大致有以下三种情况:A. when 分句前面的分句使用过去进行时。如:(1) He was still smiling when the door opened and his wife came in. 他正笑着的时候,门突然开了,他妻子走了进来。(2) I was thinking of this when I heard my name called. 我正想着这件事时,突然听到有人叫我的名字。B. when 分句前面的分句使用 was (were) about to, was (were) on the point 等。如:(1) We were about to start when it began to rain. 我们刚要出发就开始下雨了。(2) He was on the point of leaving when someone knocked at the door. 他刚要走就有人敲门。C. when 分句之前的分句用过去完成时,其中 sb had hardly / scarcely /barely when 已成为固定词组。如:(1) We had hardly fallen asleep when the bell rang. 我们刚刚入睡,铃声就响了起来。(2) He had scarcely arrived when he had to leave again. 他刚刚到达就又要离开了。表示条件,相当于 if ,引导条件状语从句。如:How can I get a job when I cant even read or write? 如果我连读和写都不会,我怎么能找到工作呢?4. 表示对比,主要有以下两种情况:A. 相当于 whereas, while, since, 意为“既然;然而”。如:(1) How can I help them to understand when they wont listen to me? 既然他们不愿听我的,我又怎么能帮助他们弄明白呢?(2)They have only three copies when we need five. 他们只有三本,而我们却需要五本。B. when 从句中使用虚拟语气,意为“本来却”。如:(1) She paid when she could have entered free. 本来可以免费入场,而她却付了款。(2) She stopped trying when she might have succeeded next time. 她本来下次有可能获得成功,但她却不再尝试了。(3) They were gossiping, when they should have been working. 他们本该工作,却在那里说别人的闲话。原因状语原因状语从句说明主句动作发生或进行的原因,一般由because,since,as等引导。because语气较强,用来说明人所不知的原因,回答why提出的问题。当原因是显而易见的或者已为人们所知,就用as 或since 。用法时间状语从句和原因状语从句的用法可以用八个字来概况:主将从现或主过从过主将从现:主句用了将来时,从句就要用现在时。主过从过:主句用了过去时,从句也要用过去时。一词多义对before从句的理解before的本意为“在之前”,根据具体语境还可理解为“还没来得及/还没有就,趁着还没就,不知不觉就,才”等。如:I had not sat long before he came back. 我没坐多久他就回来了。He almost knocked me down before he saw me. 他几乎把我撞倒才看到我。Before I could get in a word, he measured me. 我还来得及插话,他就给我量好了尺寸。Ill water the flowers before it gets dark. 我要趁着天还没黑把花浇好水。Be a pupil before you become a teacher. 先做学生,后做先生。Time passed quickly and three months went by before she knew it. 时间过得飞快,她不知不觉就在那里度过了三个月I will die before I will betray my country. 我宁可死也不会背叛我的国家。对since从句的理解1. since从句的谓语动词是终止性动词照字面意思理解。如:Ive been feeling down since I lost my job. 自从失去工作后,我的情绪一直处于低潮。2. since从句谓语动词延续性动词,且为现在完成时时,仍然按字面意思理解。如:She has never come to see me since I have lived in the city. 自从我住到城里,她就一直不来看我。3. since从句谓语动词延续性动词,且为一般过去时时,按与字面意思相反的意思理解。如:I have made great progress since I was ill. 我自病愈以来取得了很大的进步。4.since前有ever,或从句谓语动词是be且后接表示人成长过程中的某个阶段或年龄的名词、形容词时,仍然按字面意思理解。如:I have lived here ever since I was a child. 我从还是个孩子时就一直住在这儿。对till/until从句的理解1. 主句为肯定式,主句谓语动词必须为持续性动词,且该动词所表示的动作或状态一直延续到until/till从句所表示的时间为止,可译作“(直)到”。如:He waited until/till I returned. 他一直等到我回来。2. 主句为否定式(包括含no, nobody, nothing, never, hardly, little等否定词的肯定句),若主句谓语动词是非持续性动词,则该动词所表示的动作在until/till从句表示的时间开始发生。一般先译从句“直到”,后译主句,not 译成“才”,即“直到才”。如:His mother didnt leave until/till he was asleep. 直到他睡着了,他母亲才离开。Nobody can leave until/till the meeting is over. 直到散会才能离开。3. 主句为否定式,若主句谓语动词是持续性动词,则须根据上下文去理解until/till从句的含义,一般译为“直到才”或“没有到”。如:He didnt wait until/till I returned. 他没有等到我回来。She didnt sleep until/till I returned. 她直到我回来才睡着。其他 从属连词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。如:When I went into the classroom, he was reading. 当我走进教室时,他正在看书。He read a newspaper as he went along. 他边走边看报纸。We must strike while the iron is hot. 我们必须趁热打铁。I will tell you after they leave. 等他们走后我再告诉你。I told him to come back whenever he wants to. 我告诉他什么时候想回来就回来。I waited till/until she was back. 我一直等到她回来。Once time is gone, you will never get it back. 时间一旦失去就再也得不到了注意: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。如:Ill telephone you as soon as I get there. 我一到达那里就打电话给你。She said she would phone me as soon as she got there. 她说她一到达那里就给我电话。Dont get off the bus until it has stopped. 等车停稳后才下车。强调句强调句的句型是:It is (was) 被强调部分+ that (who) + 句子其他部分It was seven oclock when we reached the station.(状语从句)=It was at seven oclock that we reached the station.(强调句,定语从句)强调句和时间状语从句的区别是:时间状语从句可以去掉,不影响句子的完整性。而强调句that/who引导的句子是不能去掉的,否则句子就不完整了,单独的“It was at seven oclock”是错误的。时间状语从句和定语从句的区别其实跟上面说的是一样的,强调句型其实就是一种特殊的定语从句。本身最简单的表达法是:We reached the station at seven oclock.然后为了强调at seven oclock,就变成了强调句It was at seven oclock that we reached the staion,同时它也是定语从句:从句“that we reached the staion”修饰的是it=the time.时态问题时间状语从句常用的连词有:when,as,while,before,after,since,till,until,as soon as,once。【例】Before I could get in a word, he had already given orders.我还来不及插话,他已经吩咐下去了。After the students were all in the lab, the professor brought out three bottles.在学生们全进入实验室后,教授拿出三个瓶子来。学习时间状语从句应注意以下几点:(1)时间状语从句中一般不使用将来时态,尽管主句使用将来时态,一般使用一般现在时态或现在完成时态。【例】Ill go on with the work when I come back tomorrow.我明天回来,我将继续做这项工作。Please tell him about it when you see him back.你看到他回来,就告诉他这件事。(2)till/until引导时间状语从句,主句的谓语动词如是延续动词,可使用否定或不用否定,如果是不延续动词,必须使用否定形式。【例】He didnt go to bed until it was 12 oclock last night.他昨晚十二点才上床睡觉。They worked until it was dark.他们一直工作到天黑。(3)as soon as, the moment, every time, each time, the minute, the instant, the day, the week, the year, the first time,next time, any time, the last time, all the time, from the time, by the time, immediately, instantly, directly等表示时间的词语,后面也可以接时间状语从句,表示“一就”。【例】I recognized you the minute I saw you.我一见到你,就认出了你。By the time he was fourteen, he had built his own lab.到他十四岁的时候,他已建起自己的实验室。(4)主句使用过去进行时或过去完成时,或是was/were about to do Sth. ,后面从句使用when从句,而且谓语动词使用一般过去时,这时when不当“当时候”解,而当“突然”解。【例】They were working in the fields when it began to rain.他们在地里正干着活时,天突然下起雨来。He was about to leave when the telephone rang.他刚要走,突然电话铃响了。
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