it用法总结(高三总复习).ppt

It的用法,一、it作人称代词的用法,1.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。Itshardwork,butIenjoyit.工作很辛苦，可是我乐意干。“Whereisthedog?”“Itsinthebedroom.”“狗在哪?”“在卧室里”。,2.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Itsme。,3.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：“Whatsthis?”“Itsanewmachine.”“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,1.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、气候及温度等自然现象。1.ItisFridaytoday.2.ItwasverycoldlastMonday.3.Itisabout8:30now.4.Itisabout25kmfromLinquantoFuyang.5.ItliesinthesouthofAnhui.6.Itis40C!Yougotahighfever!,date,weather,time,distance,place,temperature,2.用于某些句型Itstimeforsth.该做某事了。Itstimetodosth.该做某事的时候了。Itstimeforsbtodosth.某人该干某事了。Its(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”)Itsfirst(second)time+that-从句.某人第几次干某事。(从句谓语用现在完成时)Its+时间段+since.自从有一段时间了。Its+时间段+before.过多长的时间才its=itwasIts+时间段+that.多久了Its+时间段+when.是在某个时刻,Itistimeforbreakfast.,Itistimetohavebreakfast.,Itistimeforustohavebreakfast.,ItisthefirsttimeIvebeenhere.,ItistwoweekssinceIsawhim,ItstenyearsbeforeIgraduated.,ItstenyearsthatIvelivedherefor,ItwastenyearsagowhenIgraduated,三、it用作形式主语,1.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，通常把真正的主语放在句末，而在句首使用形式主语it。如：Itsveryimportanttorememberthis.记住这一点很重要。Itshardworkclimbingmountains.爬山是费劲的事。Itsunknownwhenhewillcome.他什么时候来还不知道。,2.用作形式主语的的重要句型(1)it作形式主语替代不定式构成”It+be+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。【Tip】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”,2)ItisV-ed+thatItissaid(reported,learned)+thatItissaidthathehascometoBeijing.Itissuggested(ordered,demanded,insisted,commanded)+that从句中的过去分词是表示请求，建议，命令等词时，that后的从句要用虚拟语气(should+V原形).Should可以省略。译为“据建议；有命令”Itissuggestedthatthemeeting(should)beputoff.,3)Itisapity(ashame)thatThat后的从句一般用虚拟语气(should+V原形),should可以省略.表示出乎意料，译为”竟然“。没有这种意义时，则不用虚拟语气。Itisapitythatsuchathing(should)happeninyourclass.,(4)Ittakessb.+时间段+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。【Tip】此句型可以有以下多变种变体：Ittookmeanhourtowritetheletter.=Thelettertookmeanhour(towrite).=Itookanhourtowritetheletter.,(5)Itisuptosbtodosth.该由某人做某事Itsuptoyoutotomakethechoice.得由你来作选择。(6)itlook(seem,appear,happen,occur)thatasif似乎Itseemedasthoughhedidntrecognizeme.他似乎没认出我来。IthappenedthatIwasoutwhenhecalled.他打电话时我碰巧不在家。(7)Ifitwerenotfor/Ifithadntbeenfor若不是因为Ifitwerenotfortheirhelp,wecouldnthavegotoverthedifficulties.要不是他们帮助，这些困难我们不克服不了的。,四、it用作形式宾语,1.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。,2.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。Rumorhasitthatthedefenceministerwillsoonresign.据传闻，国防部长不久就要辞职。【说明】能用于此结构的动词不多，常见的有have,take,put,like等。,(2)动词+it+when(if)-从句。如：Idislikeitwhenyouwhistle.我不爱听你吹口哨。Wereallyappreciateitwhensheofferedtohelp.她来帮忙了，我们十分感激。IdpreferitifIdidnthavetodosomuchwork.要是我不必做那么多工作，好就太好了。【说明】能用于此结构的动词不多，常见的有enjoy,hate,love,like,dislike,appreciate,prefer等。,(3)动词+prep+it+that-从句。如：Seetoitthatyourenotlateagain.注意千万不要再迟到。Looktoitthatthisdoesnthappenagain.注意不要再发生这种事。Youmayrelyonitthathellcometomeetyou.你放心，他会来接你的。Icantanswerforitthathewillcome.我不能保证他会来。【说明】能用于此结构的动词不多，常见的有seeto,lookto,insiston,stickto,dependon,answerfor等。,(4)动词+it+介词短语+that-从句。如：IoweittoyouthatIamstillalive.多亏有你我才仍然活着。Itookitforgrantedthathewouldhelpus.我认为他会帮助我们的。【说明】能用于此结构的动词不多，常见的有takeitforgranted,bringittosbsattention,oweittosb等。,五、用于强调句型中,1)It+be+被强调部分+that/who(aperson)从句,ImetTomintheparkyesterday.,1)ItwasIwhometTomintheparkyesterday.,2)ItwasTomwhoImetintheparkyesterday.,3)ItwasintheparkthatImetTomyesterday.,4)ItwasyesterdaythatImetTominthepark.,2)Itisnotuntil+被强调的部分+that该句型也是强调句型，主要用于强调时间状语，译成“直到才”，可以说是notuntil的强调形式。ItwasnotuntilshetookoffherdarkglassesthatIrealizedshewasafamousfilmstar.=NotuntilshetookoffherdarkclassesdidIrealizeshewasafamousfilmstar.=Ididntrealizeshewasafamousfilmstaruntilshetookoffherdarkglasses.,六、it常用的固定搭配,1.makeit1)在口语当中相当于succeed,表示:成功、做到、说定、赶上、及时到达如:Itshardtomakeittothetopinshowbusiness.2)在口语中相当于fixthedatefor,表示“约定好时间”如:Shallwemeetnextweek?OK.WejustmakeitnextSaturday.,2.takeit/thingseasy相当于Dontworry.用来劝告别人,表示“不要慌,别担心,”Takeiteasy！Hewilldoitwell.3.Italldepends/thatalldepends在口语中,相当于ithasntbeendecidedyet,表示“那得看情况,还没有定下来”Areyougoingtothecountrysideforholiday?It/Thatalldepends.,4.Itsuptosb.在口语中,相当于itsdecidedbysb.表示“由决定,由负责,取决于”Shallwegooutfordinner？Itsuptoyou.,Itstime后的从句用虚拟语气,一、基本用法从句谓语通常用过去式表示现在或将来，有时也用过去进行时或“should+动词原形”(should不能省略)，其意为“(早)该干某事了”：IthinkItstimeyouwenttobed.我想你该睡觉了。Itstimewewentweregoing,shouldgo.我们该走了。Imgettingtired.Itstimewewenthome.我累了，我们该回家了。Ithinkitstimetheyweretaughtalesson.我想现在该给他们一点教训了。Itstimeyoulookedaheadandmadeplansforyourretirement.是你为以后想一想并对退休后的生活做出安排的时候了。,二、同义表达该是孩子们上床的时间了。Itstimethekidswereinbed.=Itstimeforthekidstobeinbed.Itistimethatthechildrenwenttobed.=Itishightimethatthechildrenshoul