名词性从句1名词性从句：在句子中起到一个名词的作用，并充当句子的主语、宾语、表语或同位语的从句。分别称之为主语从句、表语从句、宾语从句和同位语从句。了解并正确使用关联词是写好名词性从句的关键。判断依据：1.看在从句中有无具体意义；2.看在从句中有无充当成分。如有，是充当什么成分常见的关联词：which,how,why,whenever,what,whetherwho,when,whom,whose,that，whatever,whoever,where,whomever,wherever，whichever，if，however一、名词性从句的关联词的分类、词义和用法见下表：类别词义在从句中的作用连接词__________无任何词义仅起连接作用，不作成分连接词____________________是否起连接作用，不作成分连接代词________________________________________________________________________________________有各自含义引导从句，并在从句中充当主语、表语、宾语、定语连接副词________________________________________有各自含义引导从句，在从句中作状语二、从句中that和what的区别连词that只起连接作用，在从句中不作成分，不含有疑问意义，而what在从句中作成分，常含有疑问意义。表“…的东西/事情/样子/的话/的地方”，在从句中充当主语、宾语、表语。主语从句、表语从句、同位语从句中用that但不能省略。1.Iwonderifthisis______youarelookingfor.2.Ourschoolisquitedifferentfrom_______itwasbefore.3.Fathermadeapromise______ifIpassedtheexaminationhewouldbuymeacomputer.4._______Ican’tunderstandiswhyhehaschangedhismind.5.________theearthisroundisknowntousall.6.Is_____hetoldustrue?7.Ihavenodoubt_____hewillcome.8.Ihavenoidea_____hedidthatafternoon.三、who与whoever；what与whateverwhoever,whatever等引导的名词性从句不含有疑问意义，相当于名词后加一个定语从句，而who,what等引导的名词性从句都含有疑问意义。1._________wassaidheremustbekeptsecret.12._______weneedismoretime.3._______madethelongdistancecalltohimisnotimportant.4._________breaksthelawwillbepunished.四、that引导同位语从句与that引导定语从句的区别引导同位语从句的that无实际意义,不作从句的任何成分,而引导定语从句的that从句的某个成分。Hetoldmethenewsthatourteamwonthematch.(同位语从句)Hetoldmethenewsthatwasveryexciting.(定语从句)五、if与whether1.主语从句：whether引导主语从句位于句首,if引导主语从句不能位于句首Whetherwewillsucceedisstillaquestion.Itisnotknownifhewillcome.2.表语从句：只能用whether，if不能引导表语从句Theproblemiswhetherthefilmisworthseeing.3.宾语从句：whether与if有时可以换用，但下列情况只能用whether①介词后的宾语从句Everythingdependsonwhetheritisfinetomorrow.②whether…ornot的宾语从句Idon’tknowwhetherornotshe’lllikeit.③复合不定式只能用whetherTelluswhethertogoorstayhere.六、在havenoidea之后常用wh-引导同位语从句Ihavenoideawherehehasgone.Ihavenoideawhenhedidit.Ihavenoideawhathedid.七、it作形式主语或形式宾语的高级句型1．it作形式主语的常用句型(1)It＋系动词＋形容词(necessary/right/likely/unlikely/wrong/important/certain等)＋that从句(2)It＋be＋名词(短语)(apity/ashame/nowonder等)＋that从句(3)It＋be＋过去分词(said/told/reported/decided等)＋that从句(4)It＋特殊动词(seems,appears,happens,matters)＋that从句(5)Itdoesn'tmatterwho/whether/if等从句2．it作形式宾语的常用句型动词find,feel,think,consider,make,believe,guess,suppose,assume等后有宾语补足语时，则需要用it作形式2宾语，而将宾语从句后置。八、有用的句型1.…的原因是…1)Thereasonfor+名词+isthat…2)Thereasonwhy+句子+isthat…他缺席的原因是他……。1)Thereasonforhisabsenceisthat…2)Thereasonwhyhewasabsentisthat…2.This/That/Itis+where/why/how/because,表示具体的地点、原因、方式1)这就是我们为什么应该保持健康的原因。Thisiswhyweshouldkeephealthy.2)这就是我停...
