高二英语课件高二英语名词性从句2高二英语课件

名词性从句在句子中起名词作用的句子叫名词性从句.分为:主语从句、宾语从句、表语从句和同位语从句。名词从句的功能功能相当于名词词组,它在复合句中能担任主语、宾语、表语、同位语、介词宾语等，因此根据它在句中不同的语法功能，名词从句又可分为四类引导名词性从句的连接词可分为三类：1.连接代词that,whether,if不充当从句的任何成分）引导名词性从句的连接词2.连接代词：what,whatever,who,whoever,whom,whose,which.不仅起到连接一个句子的作用，同时也是从句的一个组成部分。3.连接副词：when,where,how,why引导主语从句不可省略的连词：1.介词后的连词2.引导主语从句和同位语从句的连词不可省略。同位语从句在一个更长的句子中作同位语使用的句子叫同位语从句。同位语与其前的词或短语表达的是同一事物。如：Thefactthatsheisillshouldbeconsidered.同位语从句一般在下列词的后面belief,fact,fear,hope,idea,news,problem,reason,result,possibility等。如：Ihavenoideawhenhewillreturn.不同连词引导的同位语从句引导同位语从句的连词除that外，还可以用how,when,where,why,等。Hecan’tanswerthequestionhowhegotthemoney.不同连词引导的同位语从句Ishouldliketoknowthereasonwhyyouchangedtheplan.Ihavenoideawhenshewillbeback.主语从句在另外一个句子中做主语的句子叫主语从句。Howthebookwillselldependsonitsauthor.Thatheisthebeststudentintheclassisobvious主语从句常用it作形式主语放句首因而我们常见到这种句式：It+be+n./adj/-ed从句（that,whether,etc.)例：It'sapitythatyoushouldhavetoleave.ItisgreatthatIhaveateacherlikeyou.whether与if均为“是否”但下列情况下只用whether：1.whether引导主语从句并在句首Whetherhewillcomeisnotclear.2.引导表语从句Thequestioniswhetherhe’llcome.3.whether从句作介词宾语I’mnotsureaboutwhetherwe’llwin.4.从句后有ornotWhetheryoulikeitornot,you‘llhavetodoit.表语从句在另外一个句子中作表语的句子叫表语从名。Thefactisthathehasnotbeenseenrecently.宾语从句在另一个句子中做宾语的句子叫宾语从句。Iworryaboutwhetherhecanpassthroughthecrisisofhisillness.宾语从句NowIwanttoknowwhatIcando.JohnsaidthathewasleavingforLondononWednesday名词性从句主语从句同位语从句表语从句宾语从句名词性从句动画讲解名词性从句中的一些特殊用法What=allthat不可混用:Thisisallwhatweshoulddo.Thisiswhatweshoulddo.Thisisall(that)weshoulddo.(what…东西)引导的主语从句一般不用作形式主语结构.Itisabookwhathewants.Whathewantsisabook.常见的用作形式主语的复合句结构1)Itis+名词+that从句Itisafact(ashame,apity,nowonder,goodnews,…)that…2)Itis+形容词+that从句Itisnecessary(strange,important,wonderful,Possible,likely,…)that…这类主语从句中,谓语动词多数为should+动词原形3)Itis+过去分词+that从句WhatweneediswaterWhatweneedareusefulbooks.Itissaid(reported,decided…)that…4)It+不及物动词+that从句Itseems(happened,doesn’tmatter,Hasturnedout,…)that…5)Itis(was)++that(who)ImetJohninthestreetyesterday.ItisIwho(that)amyourtruefriend宾语从句的特殊用法.1)think,believe,suppose,expect,Imagine,guessIdon’tthinkyouareright.2)think,believe,imagine,suppose,guess,Hope,I’mafraid(so/not)Doyoubelieveitwillclearup?Ibelieveso./Idon’tbelieveso.Ibelievenot.作介词的宾语that引导的宾语从句只有在Except,in,but,besides等少数介词后偶而用到:Yourarticleisallrightexceptthatitistoolong.有时在介词和其宾语从句的中间加形式宾it.I’llseetoitthateverythingisready.介词的宾语从句不能由if引导,而要用whether