高中主语从句讲解及其练习

主语从句一、主语从句的连词分三类（1）从属连词引导的主语从句（thatwhetherif）that引导的主语从句:引导词that无含义/在句中不做成分/不可以省°That引导主语从句通常用it作形式主语。例如：Thatyouwillwinthemedalseemsunlikely.Thatshesurvivedtheaccidentisamiracle.whether引导的主语从句：whether有含义（是否）/在句中不做成分/不可以省。注意：引导主语从句，不能用if不能在开头，只能用whetheroWhetherwewillholdapartyintheopenairtomorrowdependsontheweather.Whethersheiscomingornotdoesn'tmattertoomuch.（2）用连接代词引导的主语从句在由连接代词who,whose,whom,which,what,whoever,whomever,whichever,whatever引导的名词性从句中，其连接代词在句中起名词性作用，担当一定成分.例如：Whatyouneedismorepractice.Whateverwedoistoservethepeople.注：whatever/whoever的功用whatever,whoever在主语从句中不含疑问意义。它引导主语从句，并在从句中作主语、宾语、表语等。whatever=anythingthat;whoever=anyonewho。要注意和whatever,whoever引导的让步状语从句的区别。如：Whoeverbreaksthelawshouldbepunished.（主语从句）（=Anyonewhobreaksthelawshouldbepunished.）Whoeverbreaksthelaw,heshouldbepunished.（让步状语从句）（=Nomatterwhobreaksthelaw,heshouldbepunished.）（3）用连接副词when,where,why,how引导的名词性从句（其连接副词有含义,在句中作状语。）例如如:Whereweshouldleaveitisaproblem.Whentheywillcomehasn'tbeenmadepubic.三、it作形式主语的主语从句有时为了考虑句子平衡，通常在主语从句处使用形式主语it,而将真正的主语从句移至句末。这分四种情况：(1)对于以连词that引导的主语从句，通常用形式主语it替代主语从句：<a>Itis+名词+从句Itisafactthat…事实是；Itisgoodnewsthat是好消息；Itisaquestionthat………是个问题；Itiscommonknowledgethat………是常识类似的名词还有：apity；awonder；agoodthing；nowonder；surprise等。Itisamysterytomehowitallhappened.Itiscommonknowledgethatthewhaleisnotafish.ItisnosurprisethatBobshouldhavewonthegame.<b>Itis+形容词+从句Itisnecessarythat…有必要……；Itisclearthat…很清楚……；Itislikelythat…很可能……；Itisimportantthat…重要的是……类似的形容词还有：strange;natural;obvious;true;good;wonderful;possible;unlikely;quite;unusual;certain;evident;worth-while;surprising;interesting;astonishing,etc.Itisdoubtfulwhethershewillbeabletocome.Itisessentialthatheshouldbeherebytheweekend.Itseemsobviousthatwecannotgoonlikethis.Itisnecessarythatyou(should)masterthecomputer.需要注意的是这类主语从句中，谓语动词很多为(should)+动词原形”即要用虚拟语气。<c>Itis+过去分词+从句Itissaidthat…据说……；Itisreportedthat…据报道……；Ithasbeenprovedthat…已证明；Itmustbeprovedthat…必须指出类似的过去分词还有：known;estimated;expected;believed;thought;hoped;noted;discussed;required;decided;suggested;demanded;madeclear;foundout,etc.例如：Itisusedtobethoughtthatanewstarmustbeduetoacollisionbetweentwostars.Ithasnotbeenmadeclearwhenthenewroadistobeopenedtotraffic.<d>Itseems不及物动词(happened/appears/doesn''ttmatter/makesnodifference/occurred…)that…主语从句不可提前Itmakesnodifferencewhetherhewillattendthemeetingornot.ItdoesnotmatterifImissedmytrain.IthappenedthatIsawhimyesterday.(2)对于以连接代词(副词)引导的主语从句，可以使用形式主语代主语从句，也可直接在句首使用主语从句：Whethertheywouldsupportuswasaproblem.他们是否会支持我们还是一个问题。Itwasaproblemwhethertheywouldsupportus.他们是否会支持我们还是—问题。对关系代词型what引导的主语从句，通常直接将主语从句放在句首。如：Whatweneedismoney.我们需要的是钱。WhatIwanttoknowisthis.我想知道的就是这—点。有时也可将助用形式主语。如：Itisclearenoughwhathemeant.他是什么意思很清楚。如果句子是疑问句，则必须用带形式主语it的结构：Isittruethatheisthegirl'sfather?他是那女孩的父亲，是真的吗？Howisitthatyouarelateagain?你怎么又迟到了？四、连词that的省略问题引导主语从句的连词that有时可省，有时不能省，其原则是：若that引导的主语从句直接位于句首，则that不能省略；若that引导的主语从句位于句末，而在句首使用了形式主语it，则that可以省略：Thatyoudidn'tgotothetalkwasapity.很遗憾你没去听报告。(that不可省)Itwasapity(that)youdidn'tgotothetalk.很遗憾你没去听报告。(that可省)五、六、七、八、九、十、十—、十二、主语从句练习题1、Itneveroccurredtome___youcouldsucceedinpersuadinghimtochangehismind.（陕西高考）A．whichB．whatC．thatD．if、It'sobvioustothestudentstheyshouldgetwellpreparedfortheirfuture.（天津卷）A．asB．thatC．whichD．whether、somepeopleregardasadrawbackisseenasaplugbymanyothers.（2010•北京）A．WhetherB．WhatC．ThatD．How4、Itisuncertainsideeffectthemedicinewillbringabout，althoughabouttwothousandpatientshavetakenit.（2010•浙江）A．thatB．howC．whatD．whether主语从句练习题makesmistakesmustcorrectthem.A.WhatB.ThatC.WhoeverD.WhateverItworriedherabitherhairwasturninggrey.A.whileB.thatC.ifD.forWhenandwhyhecamehereyet.A.isnotknownB.arenotknownC.hasnotknownD.havenotknownisnoreasonfordismissingher.A.BecauseshewasafewminuteslateB.OwingtoafewminuteslateC.ThefactthatshewasafewminuteslateD.BeingafewminuteslateTomlikedtoeatwasdifferentfrom.A.That...thatyouhadexpectedB.What...thatyouhadexpectedC.That...whatyouhadexpectedD.What...whatyouhadexpectedwegoswimmingeverydayusalotofgood.A.If...doB.That...doC.If...doesD.That...does7.ItBobdrivesbadly.A.thinksthatB.isthoughtwhatC.thoughtthatD.isthoughtthat8.It'suncertaintheexperimentisworthdoing.A.ifB.thatC.whetherD.Howtheboydidn'ttakemedicinemadehismotherangry.A.ThatB.WhatC.HowD.Whichwecan'tgetseemsbetterthanwehave.A.What,whatB.What,thatC.That,thatD.That,whatyoudon'tlikehimisnoneofmybusiness.A.WhatB.WhoC.ThatD.Whetherwe'llgocampingtomorrowdependsontheweather.A.IfB.WhetherC.ThatD.WhereisgoingtodothejobwillbedecidedbythePartycommittee.A.ThatB.WhyC.HowD.Whowe'llfinishtranslatingthebookdependsonthetime.A.WhenB.WhyC.WhatD.Thathewon'tgothereiscleartoallofus.A.HowB.WhatC.WhyD.Thisthehousewillbebuiltwillbediscussedattomorrow'smeeting.A.IfB.WhereC.ThatD.What