原因状语从句A、引导原因状语从句的连词原因状语从句一般由从属连词because,as,since,nowthat引导。B、because,as,since和nowthat的区别:1、because“因为”,表示直接的原因,语气最强。1)why提问的句子,必须用because回答。2)because的从句常放在主句之后。3)because不能与so连用。4)because+从句;becauseof+名词短语ImissedthetrainbecauseIgotuplate.Hewasangrynotbecausewewerelatebutbecausewemadeanoise.-Whydidn’thecomeyesterday?-Becausehewasill.2、as“因为”,语气较弱,一般放在主句前,中间用逗号隔开,表示的是明显的原因。Ashewasnotwell,Idecidedtogotherewithouthim.Asitwasraininghard,wehadtobeindoors.3、since/nowthat“既然”,一般放在主句前,中间用逗号隔开,表示的是明显的原因或众所周知的事实。Since/Nowthatthismethoddoesn’twork,let’stryanother.Since/Nowthatyoufeelill,you'dbetternotgotowork.Exercise:一、填入恰当的连词1.Ididn’tgotoschoolyesterday_________Iwasill.2.________everybodyishere,let’sbeginourmeeting.3.________youareinpoorhealth,youshouldnotstayuplate.4.Iaskedhertostaytotea,________Ihadsomethingtotellher.5.________allthepassengersarehere,whydon’twestartatonce?6.Billwon’tmakeanyprogress________hedoesn’tstudyharderthanbefore.二、改写句子,保持句意不变1)Theshipchangeditscoursebecausetherewasastorm.Theshipchangeditscourse____________________________.2)Becausehewasill,hedidn’tgotoschool.Hewasill,_______hedidn’tgotoschool.3)Hecouldn'twalkbecausehislegwasbroken.Hecouldn'twalk____________his______leg.4)Icamebackbecauseitwasrainingheavily.Icameback____________the______rain.三、选择恰当的答案1.Themancan’tgetonthebus______thereisnoroomonit.A.thoughB.becauseC.untilDsothat2.______herdaughterhadn’tcomeback,______shelookedworried.A.Because,/B.Because,soC.Though,butD.Though,/3._______you’vegotachance,youmightmakefulluseofit.A.NowthatB.AfterC.AlthoughD.AssoonasKeys:A、引导原因状语从句的连词:because,as,since,nowthatB、because,as,since和nowthat的区别:1、because:“因为”,表示直接的原因,语气最强。1)why提问的句子,必须用because回答。2)because的从句常放在主句之后。3)because不能与so连用。4)because+从句;becauseof+名词短语2、as:“因为”,语气较弱,一般放在主句前,中间用逗号隔开,表示的是明显的原因。3、since/nowthat:“既然”,一般放在主句前,中间用逗号隔开,表示的是明显的原因或众所周知的事实。课堂练习:一、1.because2.Since3.As4.because5.Since6.because二、1.becauseofthestorm2.so3.becauseofbroken4.becauseofheavy三、1.B2.A3.A