《初中英语语法》PPT课件.ppt

Rewritethefollowingsentenceswithnounclausesasthesubject.1.Hisdiscoveryhasnotyetbeenproved.2.Dotheotherastronomersaccepthisideas?Itremainsaquestion.,Whathasnotyetbeenprovedishisdiscovery.Whethertheotherastronomersacceptshisideasremainsaquestion.,Discoveringusefulstructures,3.Howdidlifefirstappearedonearth?Itisstillamysterytoscientists.4.Whyistheearthbecomingwarmer?Itisanimportanttopicforresearch.,Howlifefirstappearedonearthisstillamysterytoscientists.Whytheearthisbecomingwarmerisanimportanttopicforresearch.,5.StephenHawkingat65experiencedzerogravityduringaflight.Itamazedeverybody.6.Plutoisnolongerconsideredaplanetinoursolarsystem.Whatasurprise!,ItamazedeverybodythatStephenHawkingat65experiencedzerogravityduringaflight.ItisasurprisethatPlutoisnolongerconsideredaplanetinoursolarsystem.,主语从句及引导词,主语从句在复合句中作句子的主语。引导主语从句的词有从属连词that,whether,if；连接代词who,whoever,whom,what,whatever,whose,which；连接副词when,where,how,why等。,【例句呈现】观察下列例句，指出其中所包含的主语从句及引导词:1.Whatisneededforalongtripiscarefulpreparation.该句中主语从句是_，引导词为_。,Whatisneededfora,what,longtrip,2.ThatJayZhouwillcometomycityexciteseverybody.该句中主语从句是_，引导词为_。3.Whetherwewilltravelabroadornothasnotbeendecided.该句中主语从句是_，引导词为_。,ThatJayZhouwill,Whetherwewill,cometomycity,that,travelabroadornot,whether,4.Whoeverknowsthesecretmustnttellothers.该句中主语从句是_，引导词为_。5.Itremainsapuzzlewhydinosaursdiedoutsuddenlylongtimeago.该句中主语从句是_，引导词为_。,Whoeverknowsthe,whoever,whydinosaursdied,why,secret,outsuddenlylongtimeago,【观察总结】通过分析上面例句，同学们可能会发现上面第5句中的主语从句似乎比较隐蔽。ItamazedeverybodythatStephenHawkingat65experiencedzerogravityduringaflight.其实，这也是主语从句的一种呈现方式，即：当一个句子主语过长时，可以用it作形式主语，而把真正的主语或主语从句后移至句子末尾，以保持句子的平衡。注意观察下列例句中的划线部分：,Itisnotclearhowtheaccidenthappened.Itisnothardtounderstandwhyhedidsoatthattime.Itisapitythatyoushouldhavemadesuchacarelessmistake.Itisreportedthatmorethanthirtydeathswerecausedintheaccident.,不难看出，虽然上面例句中都用it作形式主语，但句子结构却不尽相同。现将常见的由it作形式主语的句型总结如下：1.Itis+n.+that从句2.Itis+adj.+that从句，常见此类形容词有：important,necessary,clear,certain,natural,strange,obvious,likely,impossible,possible等。,3.It+特殊动词+that从句Itseems/appears.that.似乎Ithappened(tosb.)that.（某人）碰巧4.It+be+过去分词+主语从句Itissaid/reported/believed/suggested/known/provedthat.,【要点精讲】1.what与that引导主语从句观察下列例句，试着翻译例句并总结其规律。(1)Whatyoulackisself-confidence.译为：_,你所缺乏的是自信。,(2)Thatmoreandmorestudentsareadmittedintouniversitiesistrue.译为：_(3)Whatisneededfortheprogramismorewisdom.译为：_,这个项目所需要的是更多的智慧。,越来越多的学生将被大学录取的消息是真实的。,从上面例句可以看出，that引导主语从句时，在句中具有“两不”原则：一、不作句子成分；二、没有实际意义。当它引导的主语从句置于句首时，that不能省略；如果用it作形式主语，则把主语从句放在句末。,而what引导的从句则恰恰相反，what在从句中的作用为：一、作句子成分；二、除了起到引导从句的作用外还要承担具体的意义。,【巩固练习】用what或that填空。(1)_hetoldusthismorningwasjustalie.(2)_isimportanttousisenoughtime.(3)Itworriesmymom_sheisbeginningtogetalittlefat.(4)_wecantgetseemsbetterthan_wehave.,What,What,that,What,what,2.whether与if引导主语从句如果主语从句置于句首，不能用if引导，此时，需用whether。但如果用it作形式主语，而把主语从句放在句末时，也可以用if引导。,【巩固练习】用whether或if填空。(1)Itdoesntmatter_hewillcomeornot.(2)_wellgocampingtomorrowdependsontheweather.(3)Itwasdoubtful_TomreallysawSharon.(4)_TomreallysawSharonwasdoubtful.,whether/if,Whether,whether/if,Whether,3.其它引导词连接代词who,which,whom,whose有各自的具体意义，起连接作用，同时在从句中充当主语、宾语、表语、定语等；whoever,whatever,whichever在意义上更为强调，常译为“无论”；连接副词when,where,why,how等也有各自的意义，起连接作用，并在从句中作状语。,【常见错误展示】下列各句均有一处错误，请改正并分析错误的原因。1.Lighttravelsfasterthansoundiscommonknowledge.,That,that虽无词义但引导主语从句位于句首时不能省略。,if,whether都可表示“是否”,但if不能引导位于主句之前的主语从句，它可以引导位于主句之后带有形式主语it的主语从句。,2.Ifshescomingornotdoesntmattermuch.,Whether,3.Thattheprofessorsaidisofgreatimportance.4.Wherewillthetreesbeplantedhasnotbeendecided.,What,that引导主语从句时无词义。Whattheprofessorsaid表示“教授所说的”。,将will置于trees之后。主语从句要用陈述句语序。,5.Nomatterwhobreakstherulewillbepunished.6.Whenandwherethemeetingwillbeheldstillremainaquestion.,引导让步状语从句时二者可互换，但引导名词性从句时只能用whoever。,Whoever,主语从句表示单一概念时，谓语要用单数形式。,remains,7.Whatwereyourproblemsayearagohasnowbecomemine.8.Itwasrequestedthateveryonemadeaspeechatthemeeting.,has要改为have。主语从句表示复数概念时，谓语要用复数形式。,have,在“Itisrequested/ordered/suggested+that从句”中，从句要用虚拟语气，即谓语用“should+动词原形”，should可省略。,(should)make,从A、B、C、D四个选项中，选出可以填入空白处的最佳选项。1.Itisstillunderdiscussion_theoldbusstationshouldbereplacedwithamodernhotelornot.(重庆2011)A.whetherB.whenC.whichD.where,高考链接,2.Thevillagershavealreadyknown_welldoistorebuildthebridge.(江西2011)A.thisB.thatC.whatD.which,3._somepeopleregardasadrawbackisseenasaplusbymanyothers.(北京2010)A.WhetherB.WhatC.ThatD.How,4.Itneveroccurredtome_youcouldsucceedinpersuadinghimto