另学生纠结的英语考点一It be 时间 whenthatsincebefore用法辨析

高考英语状语从句的9个考点考点1：引导时间状语从句的从属连词when ,as, while, after, before, since, once, until, till, as soon as, every time/ each time, the moment, the minute, immediately, directly, instantly等。

1. be doing…when…,be about to do…when…常表示“正在……突然……”或“正要……这时……”如：I was about to fall asleep when my sister came in.I was walking along the street , when I met him.2. while 引导的从句的谓语动词必须是延续性的，并强调主句和从句的动作同时发生（或者相呼应），此外，while有时还可以表示对比。

如：We are cleaning the classroom while they are playing the football.3.The moment --- 一……就…… =as soon as , immediately,如：---Did you remember to give Mary the money you owed her?---Yes, I gave her the moment I saw her.No sooner than --- 一……就……=hardly… when如：No sooner had he arrived than he went away again.4.since，从句的谓语动词一般是短暂性动词,主句谓语动词则是延续性动词或反复发生的动作。

since引导的从句时态为一般过去时,主句时态为现在完成时或现在完成进行时。

如：She has been working for the company since she left school.她自从毕业一直在这家公司工作。

一、“It was+具体的时间点+when...”表示“当某事发生时，是几点钟或哪一年”。

此句是由when 引导的时间状语从句，而不是由when 引导的定语从句。

（2010年四川卷）Because of the heavy traffic ，it was already time for lunch break ______she got to her office.A.sinceB.thatC.whenD.until 解析在“It+is/was+具体的时间点+when...”这一结构中，主句中的it 指时间，由when 来引导这个时间状语从句。

常译为“当……的时候，是什么时间”。

所以选择C 项。

二、“It+will/would be+时间段+before...”句型中，表示“要过多久才……”，也可用于“It+may be+时间段+before...”，表示“也许要过多久才……”。

其否定形式“It will/would not be+时间段+before...”表示“没过多久（多长时间）就……”。

（1）（2008年北京卷）I ’m sorry you ’ve been waiting so long ，but it ’ll still be some time ______Brian get back.A.beforeB.sinceC.tillD.after 解析此句是由before 引导的时间状语从句，构成“It will be/was+一段时间+be -fore...”，主句中的谓语动词用肯定式时，意思是“……多久后（某人）才……”。

所以选择A项。

（2）（2010年陕西卷）John thinks it won ’t be long ______he is ready for his new job.A.whenB.afterC.beforeD.since 解析此句是由before 引导的时间状语从句，构成“It+won ’t be+时间段+状语从句”，如果主句的谓语动词是否定式时，意思是“……没过多久就……”。

It+be+时间+before/since/when/that句型辨析I since1. 翻译“It is/has been+时间段+since从句”(1)当从句谓语动词为非延续性动词时，表示这段时间从该动作开始时算起，即“自从做……以来已经多久了”。

(2)当从句谓语动词为延续性动词时，表示这段时间从动作结束时算起，即“自从不做……以来已经多久了”。

It is two years since he joined the army.他参军两年了。

(从参军那一刻算起)It is two years since he was a soldier.他退役两年了。

(从他不再是士兵算起)2. 时态主句为现在时（一般或完成），从句都是一般过去时。

主句为过去式（一般性都用was就够了），从句都是过去完成时II before1. 翻译It was/will be+时间段+before...过多长时间将发生某动作或事情；或过了多久发生了某事或动作。

It was three years before he finished the work.他花了三年才完成这项工作.It will be three years before he finishes the work.他得花三年才能完成这项工作. 2.It won't be/take long before...不久就会…It won't be long before he finishes the work.他不久就会完成这项工作.2. 时态主句为过去式（一般性都用was就够了），从句用过去时主句为将来时，从句用现在时（用一般现在时表示将来）III when1. 翻译It is + 时间点+ when…当发生什么的时候是什么时候…It was one o’clock when he came in .2. 时态主句是什么时态，从句就是什么时态3.常考与强调句的区别It was five o'clock when we arrived at the small mountain village.It was at five o'clock that we arrived at the small mountain village.强调句去掉it、be和that，余下的部分仍是一个完整的句子。

在语法填空和短文改错中it+be+时间+从句是一个常考的句式，可是学生常常会因为判断失误而选错从句的关联词。

其实只要细心这一句式还是有规律可循的。

1. It was / will be +时间段+before...表示“过多长时间才......".在否定句中，表示”没过多长时间就......“。

如：It will be two years before we get married. 我们要过两年才结婚。

It was not long before he left. 不久之后他就走了。

2. It is / has been +时间段+since... 表示”自从......以来有......时间了",此时从句时态常用一般过去时。

It is just a month since I moved here. 我搬到这儿刚好一个月。

It has been ten years since we lived here. 我们没住这儿已经十年了。

3. It was / will be + 时间点+ when...It was seven o'clock when I got to school this morning. 我是早上七点到学校的。

4. It is / was +时间状语+that... 这是强调句型的考查It was at six o'clock this morning that they set out. 他们是在今天早上六点动身的。

5. It is / was + not until... + that ... 这个句式考查的也是强调句型It was not until he took off his sunglasses that I recognised that he was a famous film star. 直到他摘下眼镜我才认出他是一个著名的影星。

It引起的几个易混淆的时间句型在学习中，同学生们对“It + be + 时间+ 从句”这个结构经常混淆不清，下面逐一进行分析。

1. It + be + 时间+ since-clause这个句型表示从since 从句谓语动作发生以后到现在或过去所经过的一段时间，意为“自从......以来已多久了”，主句多用一般现在时，从句用一般过去时，如果表示过去的情况，主句用一般过去时，从句用过去完成时，或主句用过去完成时，从句用一般过去时。

例如：It is three years since his father passed away . (从现在算起)It was 10 years since they married . (从过去算起)It had been fifteen years since she left Shanghai . (从过去算起)30 years has passed since we joined the Party . (从现在算起)2. It + be + 时间+ before-clause这个句型中的时间一般为表示一段时间的词语(如：long years , months , weeks , days ,hours , minutes ) ，主句中的谓语动词用肯定式，意为“过多长时间才......”。

主句的谓语动词是否定式时，意为“没过多长时间就......”。

主句的时态可用过去时was或将来时will be；用was 时，before从句的动词用一般过去时；用will be 时，before从句常用一般现在时。

例如：It was not long before she learned those poems by heart . 她没过多久就背会了那些诗歌。

It was long before the police arrived .过了很久警察才来。

It will be hours before he makes a decision . 要过好几个小时他才会作出决定。

高考中before和since的考点和用法Before:(1) 假设主句是一般时将来时态，从句是一般现在时.假设主句是肯定句意思是“要过多长时间才〞；假设主句是否认形式翻译成“用不了多久就〞。

It will be two weeks before everything returns to normal.两周之后一切才能恢复正常。

It won‘t be long before we meet again.用不了多久我们就会再见面的。

(2)这时假设主句是一般过去时从句也是一般过去时。

假设主句是肯定句翻译成“多长时间之后才〞，假设主句是否认形式翻译成“没过多久就〞。

如：It was some time before I realized the truth.___________________________________________。

It wasn‘t long before she became a brave solider.____________________________________________。

①Several weeks had gone by ________ realized the painting was missing.A.asB.beforeC.sinceD.when②--How long do you think it will be ________ china sends a manned spaceship to the moon？--Perhaps two or three years.A .when B.until C.that D.beforeSince:⑴第一种是从句用现在完成时，从句用一般过去时，表过去某个时间开始直到现在．如：〔1〕I have not laughed since I became deaf . 自从我聋了以后我就没有大笑过．〔2〕It's been years since I enjoyed so much as last night . 我已经好多年没有像昨晚那样痛快了．⑵第二种是主句用过去完成时，从句用一般过去时或过去完成时，表过去某个时间知道过去某个时间．如：Since she came to me , we had been happy . 自从她来到我这里，我们一直很快活．Two weeks had passed since Martin had seen him . 自从马丁见到他以后，两周已经过去了．4. He bought the TV set two years ago.It is two years _________ he ___________ the TV set. (同义句转换)5. Susan has been in this city for more than ten years. (同义句转换)______ more than ten years _____ Susan _________ to this city.1. We haven’t _______each other for a long time since we ______ last time.A．saw, met B. seen, have met C. seen, met D. seen , has met2. The old people _____ lonely at all since we ______ to visit them once a week.A. don’t feel, beginB. hasn’t felt , beganC. haven’t felt , beganD. didn’t feel , begun3. It is three years since he _________ his hometown.A. leavesB. leftC. is leavingD. has left3. The America Civil War lasted four years ______ the North won in the end.A.afterB.beforeC.whenD.then4. It was some time _______ we realized the truth.A.whenB.untilC.sinceD.before5. -Why didn‘t you tell him about the mee ting？-He rushed out of the classroom _______ I could say a word.A.beforeB.untilC.whenD.after。

强调句及Itis...thatsincebefore等句型归纳1. 为了突出或强调句中的某一成分以加强语气, 英语中通常用“It is + 被强调成分+ that/who”结构，这一结构叫作强调结构。

该结构中的 It •是无人称主语, 没有词汇意义,仅起到改变句子结构,使某一成分受到强调的作用。

如被强调的是物，用 that; 如被强调的是人, 用 who, 也可用 that。

••••强调结构中被强调的成分通常是句中的主语、宾语、地点状语或时间状语。

例如下面一句, 我们可分别对其不同成分进行强调：John wore a white suit at the dance last night.1.It was John that/who wore a white suit at the dance last night.（强调主语）2. It was a white suit that John wore at the dance last night. (强调宾语）3. It was at the dance that John wore a white suit last night. (强调地点状语）4. It was last night that John wore a white suit at the dance.（强调时间状语）••••强调结构亦可用来强调某些状语从句：It was because he was ill that he didn't come to school yesterday.（强调 because 引导的原因状语从句）It was only when the war was over in 1949 that he was able to get back home.(强调when 引导的时间状语从句）It was not until his father came back that he went to bed. (强调 until引导的时间状语从句）••••现谈谈强调结构中值得注意的几个问题：••••一. 强调结构中的时态问题••••如果被强调的成分，原句谓语动词是一般现在时或一般将来时，强调结构用 It is...that/who; 如果原句的谓语动词是过去时态，则用• Itwas...that/who; 有时还可用 be 的其它形式。

高考It +be+ 时间+ 从句”结构总结一在“It +be+ 时间+ 从句”结构中，引导从句的从属连词有before, that, since, until （till ）, when 等。

这一结构是近几年高考常考的知识点，现将它们的用法小结如下：一、It +be （not ）+ 时间段+before 从句。

其中的主句是肯定式时，意为“过多长时间才……”；主句是否定式时，意为“没过多久就……”。

例如：1. It was not long before the whole country rose and drove the Austrian soldiers from their homeland. 不久，全国人民便奋起反抗，把奥地利军队从他们的国土上赶了出去。

2. It may be five or six years before the new medicine is tested on human beings.要过五六年时间这种新药才能在人身上做试验。

3. It was two months before he designed the bridge. 过了两个月，他设计出了这座桥梁。

二、It +will be （was ）+ 时间段+until 从句若主句中用一般将来时，则从句中用一般现在时，意思是从现在起到从句中谓语动词表示的动作发生时还有多长时间；若主句中用一般过去时，则从句中也用一般过去时，意思是从过去某一时间起到从句中谓语动词表示的动作发生还有多长时间。

例如：1. It will be ten days until my birthday comes. 到我生日还有十天。

2. It was only five minutes until her husband came back from work.当时离她丈夫下班只有五分钟了。

注意：结构“一”与结构“二”在肯定句中几乎可以通用。

高考英语常考句式——it is +时间+ since (before, when)…请注意以下三个句式的区别和意思上的差异（其中的 is 根据情况可以有其他时态形式）：It is + 时间段 + since…的意思是“自从……以来有一段时间了”。

It is + 时间点 + when…的意思是“当……的时候时间是……”。

It is + 时间段 + before…的意思是“在……之前有一段时间”。

请看以下用例：It’s ten years since they got married. 他们结婚到现在已经十年了。

It was past one o’clock when he came in. 他回来时已经一点多了。

It won’t be long before they understand each other. 过不了多久他们就会互相了解的。

有时翻译可以比较灵活：It’s a long time since I met you last. 好久不见了。

(直译：自上次见到你以来有很长一段时间了。

)It’s about three years since I last played basketball. 我差不多有三年没有打篮球了。

(直译：自从我上次打篮球以来已差不多有三年了。

)请看有关高考题(答案为DDBCDC)：1.That was really a splendid evening. It’s years _________ I enjoyed myself so much. (安徽卷)A.whenB.thatC. beforeD.since2.It was some time _________we realized the truth. (山东卷)A.whenB.untilC.s inceD.before3.—Did Jack come back early last night?—Yes. It was not yet eight o’clock _________he arrived home. (福建卷)A.beforeB.whenC.thatD.until4.Scientists say it may be five or six years _________it is possible to test this medicine on human patients. (福建卷)A.sinceB.afterC. beforeD.when5.It was evening we reached the little town of Winchester. (天津卷)A.thatB.untilC.sinceD.before6.It _________ long before we _________ the result of the experiment. (上海春)A.will not be; will knowB.is; will knowC.will not be; knowD.is; know【全真模拟训练】1.It was about midnight _________ we found the lost child, crying under a tree.A.thatB.until C .when D.where2.It's some time _________ I have spoken to you about this matter.A.thatB.unlessC.si nceD.until3.It was ten _________ he stood at aunt’s door and rang the bell.A.whenB.untilC.sin ceD.that4.I think it won’t be long _________ they understand each other.A.whenB.untilC.sin ceD.before5.How pleased I am tonight! It’s years _________ we had so great a time together.A.whenB.thatC.be foreD.since6.It was some time _________ we realized how important the matter is.A.whenB.untilC.sin ceD.before7.—Did you come home very late last night?—No. It was just half past seven _________ I appeared before my parents.A.thatB.whenC.un tilD.since8.How time files! It seems like years _________ I last saw you.A.whenB.thatC.si nceD.before9.It’s more than half a century _________ the People’s Republic of China was liberated.A.whenB.thatC.si nceD.after答案：1—5 CCADD 6—9 DBCCwhen〔引导时间状语从句〕具体地说，它有以下几种含义：1．表明一个动作发生的时候，另一个动作正在进行之中。