状语从句课件

状语从句教师点拨考点精讲1时间状语从句状语从句的结构(以when为例)：1．When＋从句(，)＋主句2.主句(，)＋when＋从句一、连词：when,while,as,before,after,till,until,since,assoonas等。二、when与while的区别：when＋短暂性动作(常为一般时)或延续性动作(常为进行时)；while＋延续性动作(常为进行时)。如：WhenIstoppedmycar,apolicemancameuptome.MywifewascookingwhenIgothome.Iwasdoingmyhomeworkwhen/whilemyfatherwaswatchingTV.While/Whenweweretalking,theteachercamein.教师点拨三、till,until用法：既可以用于肯定句也可用于否定句，可以互换。如：Istayedtheretill/untilIwasaskedtoleave.Ididn'tleavetill/untilIwastoldto.四、since一般用于完成时。如：Ihaven'tgotintouchwithmyparentssinceIpartedwiththeminApril.ShehasworkedheresinceshecametoGuangdongthreeyearsago.教师点拨五、如果主句是将来时、祈使句或者表将来的情态动词句时，从句用一般现在时，有时可用现在完成时，即所谓的“主将从现”的原则。如：Don'tgetoffthebusuntilthebushasstopped/stops.IwillwritetoyouassoonasIarrive/havearrived.Canyousendmeane­mailwhenyougethome?注意：while还可以用来表达对比(不是时间状语从句)。MysisterlikesmathwhileIamfondofEnglish.(相当于并列句中的and或but)TomisgoodatthepianowhileSam(isgoodat)theviolin.教师点拨考点精讲2原因状语从句连词：because,since,as等。because表示很强的原因；since/as表示较弱的、不直接的原因，可以译成“既然”。IamworriednowbecauseIhaveleftmyhomeworkathome.Sinceeveryoneishere,let'sstartourmeeting.Asyoudon'tfeelwell,let'sstayathometoday.注意：because不与so连用。教师点拨考点精讲3条件状语从句一、连词if,unless(＝if...not),aslongas(只要)。二、一定要遵循“主将从现”的原则。如：Wewillgoforapicnicifitisfinetomorrow.Youwon'timproveyourstudyunlessyouworkhard.＝Youwon'timproveyourstudyifyoudon'tworkhard.Youwillachieveyourdreamaslongasyousticktoit.教师点拨考点精讲4让步状语从句连词：though,although,eventhough注意：不与but连用。Hecametoseemeinsuchhotweatheralthoughheisbusy.教师点拨考点精讲5目的状语从句连词：sothat,inorderthat等。目的状语从句常是情态动词句。Speakclearlysothat/inorderthattheycanunderstandyou.Igotupat5：00sothat/inorderthatIcouldcatchthefirstbus.当主句语从句主语相同时，从句还可改成不定式结构。如：Sheeatsmuchlessthanbeforesothat/inorderthatshecanlosesomeweight.＝Sheeatsmuchlessthanbeforesoasto/inordertolosesomeweight.教师点拨考点精讲6结果状语从句连词：so...that,such...that等。结构：so＋adj./adv＋that＋从句；such＋(adj.)＋n.＋that＋从句(要注意名词的可数性及其出现形式)例外：somany/much/f