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1、NounclausesasthesubjectUnit4Grammar…itwasnotclearwhethertheshapewouldlastornot.2.Whatisevenmoreimportantisthatastheearthcooleddown,waterbegantoappearonitssurface.3.Itwasnotimmediatelyobviousthatwaterwastobefundamentaltothedevelopmentoflife.Sentencesfromthisunit:HaveALk4.Sowhetherlifewillcont
2、inueontheearthformillionsofyearstocomewilldependonwhetherthisproblemcanbesolved.1.isunknown.2.isright.3.remainsunknown.4.istime.5.hasn'tbeendecidedyet.WhosewatchwaslostWhetherwewillgoforanoutingtomorrowWhatweneedWhowillbeourmonitorWhateveryoudid如果一个句子在复合句中充当一个主语,那么这个句子就是主语从句。下面每个句子都出现了主语从句,大
3、家能找到吗?连接词1.thatThattheearthmovesaroundthesuniswellknown.2.whetherWhetherhewillcomeornotisnotknownyet.3.whoWhowillbesenttherehasnotbeendecided.4.whatWhatyouneedismorepractice.5.whichWhichoneisthebestisnotclear.6.when,whereWhentheywillcomehasn'tbeenmadepublic.Wherehehasgoneisaquestion.7.why,ho
4、wWhythereisgravityishardtounderstand.HowhecanearnalivinginBritainremainsabigproblem.8.whoever,whatever,whichever可引导主语从句。Whoeverleavestheroomlastoughttoturnoffthelights.Whateverhedidwasright.Whicheverofyoucomesinwillreceiveaprize.引导主语从句连词有that,whether,who,what,whatever等。2.连词位于句首不能省略。3.主语从句大多数
5、情况下视为第三人称单数,但在关系代词what引导的主语从句后谓语动词的数要根据句意而定。小结1为了防止句子头重脚轻,通常把形式主语it放在主语位置,真正主语后置。1.Itiscertainthathewillwinthematch.2.Itistruethathehasmadeaveryimportantdiscoveryinchemistry.3.Itisverylikelythattheywillholdameeting.以that引出的主语从句,常以形式主语it引导,结构为:Itis+形容词/名词/某些动词ed+that从句。Itissaidthathehasgoneto
6、Shanghai.Itisstillamysterywhatcausedtheaccident.Itiscertainthathewillwinthematch.小结2注:在此句型中Itis+形容词/名词/某些动词ed+that从句1.形容词为:important,necessary,strange等2.名词为:apity,ashame等3.过去分词为:suggested,ordered,requested等表示建议,命令,愿望的词,谓语动词需要用should+动词原形。Itisveryimportantthatshouldlearnhowtolearn.但下列情况下只用whe
7、ther:1.引导主语从句并在句首Whetherhewillcomeisnotclear.2.引导表语从句Thequestioniswhetherhe'llcome.whether与if均为“是否”3.whether从句作介词宾语I'mnotsureaboutwhetherwe'llwin.4.引导让步状语从句时Whetheryoulikeitornot,you'llhavetodoit.1.主语从句位于句首时必须由连接词引导。2.主语从句后置时引导词that可省略。3.主语从句位于句首时,