主語從句講解及其練習

主語從句一、主語從句的連詞分三類(1)從屬連詞引導的主語從句 (thatwhetherif)that引導的主語從句：引導詞that無含義/在句中不做成分/不可以省。That引導主語從句通常用it作形式主語。例如：Thatyouwillwinthemedalseemsunlikely.Thatshesurvivedtheaccidentisamiracle.whether引導的主語從句：whether有含義(是否)/在句中不做成分/不可以省。注意：引導主語從句，不能用if不能在開頭，只能用whether。Whetherwewillholdapartyintheopenairtomorrowdependsontheweather.Whethersheiscomingornotdoesn'mattertoomuch.(2)用連接代詞引導的主語從句在由連接代詞who,whose,whom,which,what,whoever,whomever,whichever,whatever引導的名詞性從句中，其連接代詞在句中起名詞性作用，擔當一定成分.例如：Whatyouneedismorepractice.Whateverwedoistoservethepeople.注：whatever/whoever的功用whatever,whoever在主語從句中不含疑問意義。它引導主語從句，并在從句中作主語、賓語、表語等。whatever=anythingthat;whoever=anyonewho要注意和whatever,whoever弓I導的讓步狀語從句的區(qū)別。如：Whoeverbreaksthelawshouldbepunished.(主語從旬)(=Anyonewhobreaksthelawshouldbepunished.)Whoeverbreaksthelaw,heshouldbepunished.(讓步狀語從句)(=Nomatterwhobreaksthelaw,heshouldbepunished)(3)用連接副詞when,where,why,how引導的名詞性從句(其連接副詞有含義,在句中作狀語。)例如:Whereweshouldleaveitisaproblem.Whentheywillcomehasn'beenmadepubic.三、it作形式主語的主語從句有時為了考慮句子平衡，通常在主語從何處使用形式主語 it,而將真正的主語從句移至句末。這分四種情況：（1）對于以連詞that引導的主語從句，通常用形式主語it替代主語從何：<a>Itis+名詞 +從句Itisafactthat…事實是 ；Itisgoodnewsthat 是好消息；Itisaquestionthat 是個問題；Itiscommonknowledgethat 是常識類彳以的名詞還有：apity;awonder；agoodthing;nowonder；surprise等。Itisamysterytomehowitallhappened.Itiscommonknowledgethatthewhaleisnotafish.ItisnosurprisethatBobshouldhavewonthegame.<b>Itis+形容詞 +從句Itisnecessarythat…有必要 ；Itisclearthat???很清楚 ；Itislikelythat???很可能 ；Itisimportantthat???重要的是 類似的形容詞還有： strange;natural;obvious;true;good;wonderful;possible;unlikely;quite;unusual;certain;evident;worth-while;surprising;interesting;astonishing,etc.Itisdoubtfulwhethershewillbeabletocome.Itisessentialthatheshouldbeherebytheweekend.Itseemsobviousthatwecannotgoonlikethis.Itisnecessarythatyou（should）masterthecomputer.需要注意的是這類主語從句中，謂語動詞很多為“（should）+動詞原形”，即要用虛擬語氣。<c>Itis+過去分詞+從句Itissaidthat…據(jù)說 ;Itisreportedthat…據(jù)報道 ；Ithasbeenprovedthat???已證明 ；Itmustbeprovedthat…必須指出 類似的過去分詞還有： known;estimated;expected;believed;thought;hoped;noted;discussed;required;decided;suggested;demanded;madeclear;foundout,etc.例如：Itisusedtobethoughtthatanewstarmustbeduetoacollisionbetweentwostars.Ithasnotbeenmadeclearwhenthenewroadistobeopenedtotraffic.

<d>Itseems不及物動詞(happened/appearsdoesn''ttmatter/makesnodifference/occurred…)that…主語從何不可提前Itmakesnodifferencewhetherhewillattendthemeetingornot.ItdoesnotmatterifImissedmytrain.IthappenedthatIsawhimyesterday.(2)對于以連接代詞(副詞)引導的主語從句，可以使用形式主語代主語從句，也可直接在句首使用主語從句：Whethertheywouldsupportuswasaproblem.他4」是否會支持我4」還是——個問題。ItwasaproblemwhethertheywouldsupportusftHi」是否會支持我4」還是——個問題。(3)對關(guān)系代詞型what引導的主語從句，通常直接將主語從句放在句首。 如：Whatweneedismoney.我們需要的是錢。WhatIwanttoknowisthis.我想知道的就是這一點。有時也可將助用形式主語。如：Itisclearenoughwhathemeant.他是什么意思很清楚。(4)如果句子是疑問句，則必須用帶形式主語 it的結(jié)構(gòu)：Isittruethatheisthegirl'sfather?他是那女孩的父親，是真的嗎Howisitthatyouarelateagain?你怎么又遲至U了四、連詞that的省略問題引導主語從句的連詞that有時可省，有時不能省，其原則是： 若that引導的主語從句直接位于句首，則that不能省略；若that引導的主語從句位于句末，而在句首使用了形式主語it,則that可以省略：Thatyoudidn'tgotothetalkwasapity.很遺憾你沒去聽報告。(that不可省)Itwasapity(that)youdidn'tgotothetalk.很遺憾你沒去聽報告。(that可省)五、高考題：1、Itneveroccurredtomeyoucouldsucceedinpersuadinghimtochangehismind.(陜西高考)A.whichB.whatC.thatD.ifA.whichB.whatC.thatD.ifIt'sobvioustothestudents theyshouldgetwellpreparedfortheirfuture.（天津卷）A．a(chǎn)s B．that C．which D．whether somepeopleregardasadrawbackisseenasaplugbymanyothers.（2010?北京）A．WhetherB．What C．That D．HowItisuncertain sideeffectthemedicinewillbringabou，talthoughabouttwothousandpatientshavetakenit.（2010浙江）A．that B．how C．what D．whether主語從句練習題makesmistakesmustcorrectthem.A.WhatB.ThatC.WhoeverD.WhateverItworriedherabit herhairwasturninggrey.A.whileB.thatC.ifD.forWhenandwhyhecamehere yet.A.isnotknownB.arenotknownC.hasnotknownD.havenotknown isnoreasonfordismissingher.A.BecauseshewasafewminuteslateB.OwingtoafewminuteslateC.ThefactthatshewasafewminuteslateD.Beingafewminuteslate Tomlikedtoeatwasdifferentfrom .A.That…thatyouhadexpectedB.What…thatyouhadexpectedC.That…whatyouhadexpectedD.What…whatyouhadexpectedwegoswimmingeveryday usalotofgood.A.If...doB.That...doC.If...doesD.That...doest Bobdrivesbadly.A.thinksthatB.isthoughtwhatC.thoughtthatD.isthoughtthatt'suncertain theexperimentisworthdoing.A.ifB.thatC.whetherD.howtheboydidn'ttakemedicinemadehismotherangry.A.ThatB.WhatC.HowD.Whichwecan'tgetseemsbetterthan wehave.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. youcomeornotisuptoyou.A.WhatB.IfC.WhyD.Whethermakesmist