时间从句 的区别 完整解释

1、It+时间+从句”考点透视请看下面一道题:The field research will take Joan and Paul about five months; it will be a long time _ we meet them again.A. after             B. before             C. since&#

2、160;                  D. when这是2007年安徽的一道高考题，其实质上是通过“it + be+从句”这一句型来考查了连词的用法。在该结构中连词的选择是有规可循的，主要是由主句、从句中的谓语动词的时态来确定的。下面通过下表比较（尤其是对主从中时态的比较）就能很容易的掌握。结构从句中谓语动词的形式含义例句It is +时间段+since从句一般过去时（到现在为止）做某事已有多长时间了It is three yea

3、rs since the war broke out.It was+时间段+since从句过去完成时（到过去某时为止）做某事已有多长时间了It was two years since he had left here.It was +时间段+before从句一般过去时过了多长时间才It was a long time before I got to sleep again.It was not +时间段+before从句一般过去时没过多长时间就It wasnt long before he told me about this affairIt will be +时间段+before从句一般现

4、在时要过了多长时间才It will be five years before we meet again.It will be not +时间段+before从句一般过去时没过多长时间就It wont three hours before he arrives at the bus stop.It is/was +时间点+when引导的定语从句 做某事的时间是什么时间It was eight oclock in the morning when he went shopping.It is/was+时间状语+that引导的强调句 正是在某个时间，某事发生了It was at

5、 eight oclock in the morning that he went shopping.Its time that+从句一般过去时（或should+动词原形）是该做某事的时候了It is time that I went (should go) to pick up his daughter.It is the first/second/third time +that从句现在完成时某人第一/二/三次做It is my first time (that) I have visited the Great Wall.It/This/That was the first/second

6、/third time +that从句过去完成时某人第一/二/三次做It was the second time that the film had been shown in this cinema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：1、 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

7、"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. 2. It may be five or six years before the new medicine is tested on human beings.3. It was two months before he designed the bridge. 2、 It +will be （ was ） + 时间段 +until 从句 若主句中

8、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. 2. It was only five minutes until her husband came back from work.注意：结构"一"与结构"二"在肯定句中几乎可以通用。但是，若从句中谓语动词表示的将来动作一定或预期肯定会发生，则多用

9、until 引导从句；若从句中谓语动词表示的将来动作在客观上并非一定要发生时，则多用 before 引导从句。3、 It +is / has been （ was ） + 时间段 +since 从句 在这一结构中，主句常用一般现在时、现在完成时或一般过去时。如果 since 引导的状语从句中的谓语动词为非延续性动词，则表示"自从状语从句中的动作发生以后，时间过不了多久"。例如：1. It is two years since Jim came to China. 2. It has been three years since they got married.如果 sin

10、ce 从句中的谓语动词为延续性动词，则表示"自从从句谓语动词表示的动作结束以来，时间已过了多久"。例如：3. It is / has been a year since he smoked.4、 It +is / was + 时间点 +when 从句 在这一结构中，时间之前没有介词，从句为 when 引导的时间状语从句。从句常用一般过去时，意为"当某事发生时，时间是."。例如：1. It was October 1st, 1949 when the People's Republic of China was founded.2. What ti

11、me was it when you got to school?五 . It is /was + 时间状语 +that 从句 这是一个强调句型，被强调的部分是时间状语。表示"正是在某个时间，某事发生了"。例如1. It was ten years ago that he joined the army. 2. It was yesterday afternoon that I met him in the street.6、 It is / was +first time / second time + （ that ）从句 在这一结构中， time 前面常用序数词来修饰

12、， that 引导的是定语从句，从句中常用现在完成时态或过去完成时态，表示"这是第.次做某事"。例如：1. This is the first time in my life that I have come to Beijing.2. It was the third time that he had asked the same question. 7、 It is （ high ） time +that 从句 在这一结构中， that 从句中的谓语动词常用虚拟语气，即" should + 动词原形"或用动词的过去式，表示"该做某事了&qu

13、ot;。 例如：1. It is high time that we began our work. 2. It is time that he left the place.【链接训练】例1：Itisalmostfiveyears_wesaweachotherlasttime.(05北京) A.before B.since C.after D.when例2：-DidJackcomebackearlylastnight？ -Yes.Itwasnotyeteighto'clock_hearrivedhome. A.beforeB.whenC.thatD.until总结二这类考题出现频率较

14、高，考生又极易混淆，在复习中做出归类非常必要：1.Itis/hasbeen+时间段+since+一般过去时 例1：Itis/hasbeen10yearssincehecamehere.这类句型可转化为： =Tenyearshaspassedsincehecamehere. 这一句型可扩展为：Itwas+时间段+since(从句用过去完成时) 例2：ItwasyearssincehehadarrivedinChina.(过去是+since+过去完成时) 需要注意的是since从句的谓语动词一般是非延续性动词，但有时也可用延续性动词或表示状态的词，此时需要注意句子的翻译：例3：Itisthreey

15、earssinceshecametoourclass. Itisthreeyearssinceshewasinourclass.2. It+was+时间点+whenclause(从句谓语用一般过去时) willbe+时间点+whenclause(从句谓语用一般现在时表将来)例1：Itwasalreadyeveningwhenhecameback.例2：Itwillbemiddaywhentheygethome.3. It+will(not)be+时间段+before+现在时 was(not)+时间段+before+过去时例1：Itwillbeanotheryearbeforehecomeshe

16、re.例2：Itwassometime_werealizedthetruth.(2005山东24) A.whenB.untilC.sinceD.before该句型中before前常用时间段，表示".之后才.""在.之前就."有时before前也可以用时间点，此时突出表示动作的变化。试比较：例3：ItwaseveningbeforewereachedthelittletownofTailstocks. 当我们到达Tailstocks时已经黑了。(到达前天还没有黑)4. It/Thisis+the+序数词+时间+定语从句(从句用完成时)例1：Itisthef

17、irsttime(that)Ihavebeenhere.(定语从句) 该句型可扩展为：Itwas+序数词+时间+定语从句(从句用过去完成时) 例2：Itwasthesecondtimehehadbeenoutwithheralone.例3：It'sthesecondtimeyou_latethisweek. A.arriveB.arrivedC.have arrivedD.had arrived 5. Itis+(high)time+that+did(虚拟语气) 例1：Itis(high)time(that)westoppedpollution. 其中that引导得从句中也可用shou

18、ld+V(原型)例2：Itis(high)time(that)youcame/shouldcomehere. 写作中表示建议时也常可用这类句型。例3：It'shightimewetookmeasurestosolvethisproblem.注意应将以上5种句型与强调时间的强调句型的区别。6. Itbe+时间(被强调部分)+that例1：Itwasat6o'clockthatweheardthenoise.例2：Itwas3yearsagothathejoinedthearmy. 最简单的判断方法是：当表示时间的词前有介词或者后有副词时，一定是强调结构，必用that。 试比较下面

19、句式与强调句的不同之处： Itwasalreadyteno'clockwhenhearrived. ItistenyearssinceImetyoulast. Itwasquitesometimebeforehefoundtheelephantatall. 以上几句中时间前无介词后没副词故不是强调句型。【链接训练】1.Itwasnotuntil1936_basketballbecamearegularpartoftheOlympicGames. A.thatB.whenC.whichD.then2.Itwillnotbe_wemeetagain. A.longbefore B.befo

20、relong C.soonafter D.shortlyafter3.Hewasnearlydrownedonce. Whenwas_？ _wasin1998whenhewasinmiddleschool. A.that;ItB.this;ThisC.this;ItD.that;This4.Itwasevening_wereachedthelittletownofWinchester.(04天津) A.that B.until C.sinceD.before5.Scientistssayitmaybefiveorsixyears_itispossibletotestthismedicineon

21、humanpatients. A.sinceB.afterC.beforeD.when6.Itwas_ImetMr.SmithinLondon.A.manyyearsthatB.formanyyearssince C.sincemanyyearsagowhenD.manyyearsagothat7. -Whatwasthepartylike？ -Wonderful.It'syears_Ienjoyedmyselfsomuch.A. afterB.beforeC.whenD.since8. Itwasabout600yearsago_thefirstclockwithafaceandan

22、hourhandwasmade.A.thatB.untilC.beforeD.when9. I'm sorry you've been waiting so long, but it'll still be some time _ Brian get back. A. before B. since C. till D. After10.-DidJackcomebackearlylastnight？ -Yes.Itwasnotyeteighto'clock_hearrivedhome. A.beforeB.whenC.thatD.until总结三这类考题出现频率

23、较高，考生又极易混淆，在复习中做出归类非常必要：1. Itis/hasbeen+时间段+since+一般过去时 例如：Itis/hasbeen5yearssincehecameto our school. 这一句型可引申为：Itwas+时间段+since(从句用过去完成时) 如：Itwas10 yearssincehehadarrivedinChina. 需要注意的是since从句的谓语动词一般是非延续性动词，但有时也可用延续性动词或表示状态的词，此时需要注意句子的翻译： 例如：Itisthreeyearssinceshecametoourclass. Itisthreeyearssinces

24、hewasinourclass.总之，在翻译此类句子的时候我们要记住一点，那就是"自从这一动作结束以来"，只要记住这一点我们就比较好理解句子了。2. It+was+时间点+whenclause(从句谓语用一般过去时) It willbe+时间点+whenclause(从句谓语用一般现在时表将来) 例如：Itwasalreadyeight o'clockwhenhecameback. Itwillbemiddaywhentheygethome. 3. It+will(not)be+时间段+before+现在时 It was(not)+时间段+before+过去时 例如

25、：Itwillbeanotheryearbeforehecomeshere. Itwassometime_werealizedthetruth.(05山东24) A.whenB.untilC.sinceD.before 4. It/Thisis+the+序数词+时间+that从句(从句用完成时) 例如：ItisthefirsttimethatIhavebeenhere. 该句型可引申为：Itwas+序数词+时间+that从句(从句用过去完成时) 例如：Itwasthesecondtimethat hehadbeenoutwithheralone.5. Itis+(high)time+that+

26、did(虚拟语气) 例如：Itis(high)time(that)westoppedpollution. 其中that引导得从句中也可用should+V(原型) 如：Itis(high)time(that)youcame/shouldcomehere. 写作中表示建议时也常可用这类句型。 如：It'shightimewebroke away from the bad habits and formed good ones. 注意应将以上5种句型与强调时间的强调句型的区别：6. Itbe+时间(被强调部分)+that 如：Itwasat6o'clockthatweheardthe

27、noise.（强调句） Itwas3yearsagothathejoinedthearmy.（非强调句） 最简单的判断方法是：当表示时间的词前有介词或者后有副词时，一定是强调结构，必用that。 试比较下面句式与强调句的不同之处： Itwasalreadyteno'clockwhenhearrived. ItistenyearssinceImetyoulast. Itwasquitesometimebeforehefoundtheelephantatall. 以上几句中时间前无介词后没副词故不是强调句型。总结四探究语法填空中"It be +时间+conj"句型 在各

28、类考试和历届高考试题中"it+be+time+conj"句型以不同的形式出现,往往使同学们顾此失彼,一头雾水,原因在于没有搞清楚各个句型的特点及实质,现结合历届高考题分别予以探究。(一)It is +时间段+since+从句It has been +时间段+since+从句 此句型的要点：(1) 注意since前后句子时态.since前的时态为is或has been,后的时态为一般过去时Eg: It is(has been) ten years since I joined the army 译为:(2) since后的动词若为延续性或状态性动词,应译为否定或相反,若为短暂

29、性动词按字面意思翻译.Eg: It is(has been) ten years since I was a teacher =It is(has been) ten years since I left the army 译为:.It is ten years since I smoked =It is ten years since I stopped smoking 译为:【链接训练】:1、What was the party like？Wonderful. It's years_ I enjoyed myself so much A. after B.before C:when

30、 D:since2、 I live in Beijing now, that's to say, it's ten years since I _Beijing. A:lived in B:left for C:left D:was in3、 I'm a teacher now, that's to say, it is ten years since I_ a teacher. A: have been B: was C:became D:turned （2） It will be +时间段+before+一般现在时的从句 "要过多久/ 不久.才.&

31、quot; It was +时间段+before+一般过去时的从句 "过了多久才." "before"句型和"since"句型的共性都加时间段,差异在于前后的时态和翻译。Eg: It will be ten years before I return home. 译为: It was ten years before he found his lost boy. 译为:【链接训练】:1、It is reported that it may be two or three months_it is possible to test this medicine on animals.A:since B:after C:before D:when2、 How long do you think it will be _ China sends a manned spaceship to the moon？ Perhaps two or th