主語從句以及練習題

主語從句以及練習題主語從句：做主語用的名詞性從句，因其在復合句中做主語，又稱主語從句，引導主語從句的有連詞that，whether，連接代詞who，what，which，連接副詞when，where，how，why等。1）連詞：that，whether等.that引導主語從句只起引導作用，本身無實際意義，在主語從句中不充當任何成分，但不能省略。Thathewillwiniscertain.他肯定會贏。Whetherhe’llcomehereisn’tclear.他是否會來這里還不清。注意:由that引導的主語從句有時為了使句子結(jié)構(gòu)平衡,避免“頭重腳輕”,常用it作形式主語,而把從句放在后面。例如:1.ThathewillrefusethispieceofadviceisimpossibleItisimpossiblethathewillrefusethispieceofadvice.it為形式主語2.Thattheyshouldlikeeachotherisnatural.Itisnaturalthattheyshouldlikeeachother.這樣就構(gòu)成了下面一些常用句型:1)Itis+n.+從句Itisapity/shamethat...遺憾的是……Itisasurprisethat…令人驚奇的是…Itisafactthat……是事實Itiscommonknowledgethat……是常識2)Itis+adj.+從句It’scertainthat…肯定…Itispossiblethat...很可能……Itisunlikelythat...不可能……Itisobviousthat…很明顯…Itisnecessary\important\natural\...that…3)It+不及物動詞+從句Ithappenedthat...碰巧……Itoccurredtomethat…我突然想起…4)It+be+過去分詞+從句Itissaidthat...據(jù)說……Itisknowntoallthat...眾所周知……Itisreportedthat...據(jù)報道……Itisbelievedthat...據(jù)信……;人們相信……Itissuggestedthat+(should）do...建議……Itmustbeadmittedthat…必須承認……Itcannotbedeniedthat…不可否認……Itmustbepointedoutthat…需指出的是……2.連接代詞who，what，which,whatever,whichever,whoever(Who,whom,which,what可以和ever構(gòu)成合成詞，和what一樣引導從句，ever起到強調(diào)作用。此類主語從句不能用形式主語it引導，它們在句子中擔任成分，不能省略，語序為陳述語序)Whoeverbreaksthelawwillbepunished3)連接副詞when，where，how，why等。Whentheywillleaveisnotdecided.Wheresheisfromisunknown注意:1）主語從句在句首時，必須由連接詞引導，不能省略這些連接詞；但是如果用it做形式主語，而把主語從句放在句末時，從屬連詞that可以省略。誤：Theyshouldlikeeachotherisnatural.正：Thattheyshouldlikeeachotherisnatural.正：Itisnatural(that)theyshouldlikeeachother.2)如果主語從句放在句首，不能用if引導，但是如果用it做形式主語，而把主語從句放在句末時，也可以用if引導.或把if改為whether誤：IfMaryreallyheardhimisreallydoubtful.正：ItwasdoubtfulifMaryreallyheardhim.正:WhetherMaryreallyheardhimisreallydoubtful主語從句的規(guī)律：找出下列句子中的錯誤，并總結(jié)規(guī)律例1.Whenwillhecomeisnotknown.正：Whenhewillcomeisnotknown規(guī)律一、主語從句一律用陳述語序，即主語在前，謂語在后。例2.Hewillnotcometothemeetingthiseveningistrue正：Thathewillnotcometothemeetingthiseveningistrue.規(guī)律二、連詞that在從句中無實際意義，但不能省略。例3.Ifthemeetingwillbeputoffhasnotbeendecidedyet正：Whetherthemeetingwillbeputoffhasnotbeendecidedyet.規(guī)律三、whether可以引導主語從句，放在句首，但if不能例4.Thatwhetherhewillhelpothersisafact.正：Thathewillhelpothersisafact.規(guī)律四、主語從句中的連詞不能重疊使用。例5.Whenhewillcomeareapuzzle.正：Whenhewillcomeisapuzzle.規(guī)律五、含主語從句的主句謂語動詞多用單數(shù)第三人稱形式。1.Whatheneedsisthatbook.2.Whatheneedsaresomebooks.規(guī)律六、what引導的主語從句，可根據(jù)表語決定主句動詞的單復數(shù)形式。規(guī)律七、主語從句為了避免頭重腳輕現(xiàn)象，用it做形式主語，而把從句放在后面。Thattheearthturnsaroundthesunisknowntoall.Exercises:1.Dhashelpedtosavethedrowninggirlisworthpraising.A.WhoB.TheoneC.AnyoneD.Whoever2.ItwasAhesaiddisappointedme.A.what;thatB.that;thatC.what;whatD.that;what3.Bwe’llgocampingtomorrowdependsontheweatherA.IfB.WhetherC.ThatD.Where4.Ahesaidatthemeetingsurprisedeverybodypresent.A.WhatB.ThatC.ThefactD.Thematter5.Bwastoreturntoschool.A.ThatreallyinterestedhimB.WhatreallyinterestedhimC.WhichreallyinterestedhimD.Thatinteresthimreally6、_A__hemadeanimportantspeechatthemeetingwastrue.A.ThatB.WhyC.WhatD.How7、_B__we’llgocampingtomorrowdependsontheweather.AIfBWhetherCThatDWhere8.__D_isknowntousallthatAmericaisadevelopedcountry.AWhic