(完整版)it用法完全归纳

isisit用法完全归纳一、it作人称代词的用法指事物 作为人称代词，it可以除人以外的一切事物或动物。如：Idroppedmywatchanditbroke.我把手表掉在地上摔坏了。It’shardwork,butIenjoyit.工作很辛苦，可是我乐意干。“Whereisthedog?”“It’sinthebedroom.”“狗在哪?”“在卧室里”。指人 it指人主要用于指不性别不明的婴儿或用于确认某人的身份。如： Isitaboyoragirl?是男孩还是女孩?Thereisaknockonthedoor.Itmustbethepostman.有人在敲门，一定是邮递员。【说明】在答语中，常用来指本人，如说It’sme。代替某些代词 代词 it 还可用于代替指示代词this,that 以及复合不定代词something,anything,nothing等。如： “What’sthis?”“It’sanewmachine.”“这是什么?”“是一种新机器”。Nothingiswrong,isit?没出什么问题，是吗?二、it作非人称代词的用法基本用法 it作非人称代词的用法，主要用于指时间、距离、价值、天气、气候及温等自然现象。如： It’stoolatetogotherenow.现在去那儿已经太迟了。Itrainedalldayyesterday.昨天下了一天的雨。Itcangetveryhothere.这里有时会很热。用于某些句型 It’stimeforsth.该做某事了。It’stimetodosth.该做某事的时候了。It’stimeforsbtodosth.某人该干某事了。It’s(about/high)time+that-从句.某人该做某事了。(从句谓语用过去式，有时也用“should+动词原形”)It’sfirst(second)time+that-从句.某人第几次干某事。(从句谓语用现在完成时)It’s+时间段+since-从句.自从……有一段时间了。It’s+时间段+before-从句.过多长的时间才……三、it用作形式主语基本用法 当不定式、动名词、从句等复杂成分用作句子主语时，为保持句子平衡，常把真正的主语放在句末，而在句首使用形式主语it。如： It’sveryimportanttorememberthis.记住这一点很重要。It’shardworkclimbingmountains.爬ft是费劲的事。It’sunknownwhenhewillcome.他什么时候来还不知道。用作形式主语的的重要句型Itbe+adj.for(of)sbtodosth某人做某事……Itishardforhimtomakeuphismind.他很难下定决心。Itwasfoolishofhertosaysuchathing.她说那样的话，真是太蠢了。【说明】介词of与for的区别是：of用于指某人的性格、属性、特征等，介词for表示对象，意为“对……来说”Ittakessb++todosth.某人做某事花了……时间Ittakesyearstomasteranewlanguage.要花多年的时间才能掌握一门新的语言。【说明】此句型可以有以下多变种变体：Ittookmeanhourtowritetheletter.=Thelettertookmeanhour(towrite).=Itookanhourtowritetheletter.我写这封信花了一个小时。Itisuptosbtodosth.该由某人做某事It’suptoyoutotomakethechoice.得由你来作选择。itlook(seem,appear,happen,occur)that[asif]„似乎……Itseemedasthoughhedidn’trecognizeme.他似乎没认出我来。IthappenedthatIwasoutwhenhecalled.他打电话时我碰巧不在家。Itis(was)被强调部分that(who)+句子其他部分.此结构强调的成分仅限于主语,宾语和状语.Itisfromthesunthatwegetlightandheat.ItwasnotuntilIhadreadyourletterthatIunderstoodthetruestateofaffairs.典型例题1）Itwaslastnight Isawthecomet(彗星).A.thetimeB.whenC.thatD.which答案C.强调句的结构是：It+be+强调部分+that(who)+主谓句.强调句的连词只有两个,that和who.当强调的部分是人,且为句子的主语时,才用"who",其余用that.原句：Myfatherdidtheexperimentinthelabyesterdayevening.强调主语：Itwasmyfatherwhodidtheexperimentinthelabyesterdayevening.强调宾语：Itwastheexperimentthatmyfatherdidinthelabyesterdayevening.强调时间：Itwasyesterdayeveningthatmyfatherdidtheexperimentinthelab.(注意不用when)强调地点：Itwasinthelabthatmyfatherdidtheexperimentyesterdayevening.4、it用作形式宾语基本用法当不定式、动名词、从句等复杂成分用作宾语且其后跟有宾语补足语时，通常会在宾语补足语前使用形式宾语，而将真正的宾语移至句末。其基本结构为“动词+it+宾语补足语+不定式(动名词或从句)”。如： Ifinditdifficulttodothejobwell.我发现做好这件事不容易。Ithinkitbestthatyoushouldstayhere.我认为你最好住这儿。Wethinkitnousecomplaining.我们认为抱怨是没有用的。用作形式宾语的几个特殊结构(1)动词+it+that-从句。如： Ilikeitthatyoucame.你来了，我很高兴。Itakeit(that)hewillcomeontime.我认为他会准时来的。Youcanputitthatitwasarrangedbefore.你可以说这是以前安排的。【说明】能用于此结构的动词不多，常见的有takeitforgranted,bringittosb’sattention,oweittosb等。It的用法练习一．单项选择。WasitduringtheSecondWorldWar heA.that B.while C.inwhich D.thenIs necessarytotakeoffourshoeswhenweenterthelab?A.everyone B.this C.her D.itIs possibletoflytothemooninaspaceship?A.now B.that C.it D.manIdon’tthink possibletomasteraforeignlanguagewithoutmuchmemorywork.A.this B.that C.its D.itSheheardofaterriblenoise, broughtherheartintoher A.it B.which C.this D.thatAlicereceivedaninvitationfromherboss, cameasa surprise.A.it B.that C.which D.heDoes matterifhecan’tfinishthejobontime?A.this B.that C.he D.it（补充定语从句中which还有一种特殊用法，它可以引导从句修饰前面的整个主句，代替主句所表示的整体概念或部分概念。在这种从句中，which可以作主语，也可以作宾语或表语，多数情况下意思是与andthis相似，例如： Hesucceededinthecompetition,whichmadehisparentsveryhappy.）Tom’smotherkepttellinghimthatheshouldworkharder,but didn’thelp.A.he B.which C.she D.itTheweatherturnedouttobeverygood, wasmorethanwe couldexpect.A.what B.which C.that D.it isafactthatEnglishisbeingacceptedasaninternational language.A.There B.This C.That D.It12.Itwasabout600yearsago thefirstclockwithafaceand anhourhandwasmade.A.that B.until C.before D.when13.Ihate whenpeopletalkwiththeirmouthsfull.A.it B.that C.these D.themItwasonlywhenIrereadhispoemsrecently Ibeganto appreciatetheirbeauty.A.until B.that C.then D.soItistheabilitytodothejob mattersnotwhereyoucome fromorwhatyouare.A.one B.that C.what 16.It youthat toblame.A.is;is B.is;are C.are;are D.are;is17.Was thatIsawlastnightattheconcert?A.ityou B.notyou C.you D.thatyou18. electricityplayssuchanimportantpartinourlife?A.Whyisitthat B.Whyisit C.Whyitisthat D.Whyisthat19.Itwas he