www.themegallery.comCompanyLogoas引导限制性定语从句和非限制性定语从句1.引导限制性定语从句多用于以下三个结构：such…as,thesame…as,as(so)…as，可以代替先行词是人或物的名词作主语、宾语、表语或状语等。Suchpeopleaswerementionedbyhimwerehonest.Ilikethesamebookasyoudo.I’veneverseensuchaclevermanasheis.Ishalldoitinthesamewayasyoudid.www.themegallery.comCompanyLogo2.such(so)…as引导定语从句而such(so)…that引导结果状语从句。TheytalkedinsuchsimpleEnglishaschildrencouldunderstand.TheytalkedinsuchsimpleEnglishthatchildrencouldunderstandit.www.themegallery.comCompanyLogo3.thesame…that与thesame…as在意思上是不同的。ThisisthesamebagasIlostyesterday.(相似物)ThisisthesamebagthatIlostyesterday.(同一物)www.themegallery.comCompanyLogo4.as也可单独使用，引导非限制性定语从句，作用相当于which。例如：Hewaslateforschool,as/whichwasusualwithhim．Ilivealongwayfromwork,as/whichyouknow.www.themegallery.comCompanyLogoas和which引导非限制性定语从句的区别1.as引导的非限制性定语从句位置较灵活,可以位于主句前面,中间或后面，一般用逗号与主句隔开,但which所引导的非限制性定语从句只能放在主句之后。Asisknowntoall,theearthisround.Theearthisround,asisknowntoall.Theearthisround,whichisknowntoall.www.themegallery.comCompanyLogoas和which引导非限制性定语从句的区别2.当主句是否定句时，只能用as。Spidersarenotinsects,asmanypeoplethink.www.themegallery.comCompanyLogoas和which引导非限制性定语从句的区别3.如果要说明两者有相似之处时通常用as,表达“正如（情形或事实所表示）的那样、像……的一样”的意思。Sheisafinesinger,ashermotherusedtobe．Asweknow,smokingisharmfultoone'shealth.www.themegallery.comCompanyLogoas和which引导非限制性定语从句的区别4.as代表前面的整个主句并在从句中作主语时,从句中的谓语必须是系动词;若为行为动词(happen除外),则从句中的关系代词只能用which。Hewasabsent，asisoftenthecase．Itrainedhardyesterday,whichpreventedmefromgoingtothepark.www.themegallery.comCompanyLogoas和which引导非限制性定语从句的区别5.as所引导的从句所表达的语意须和主句一致，而which则无此限制。Shehasmarriedagain,aswasexpected．Shehasmarriedagain,whichwasunexpected．
