高一英语语法《状语从句》PPT课件

状语从句按其意义和作用可分为:1.时间状语从句2.地点状语从句3.原因状语从句4.目的状语从句5.结果状语从句6.条件状语从句7.方式状语从句8.比较状语从句9.让步状语从句引导时间状语从句的从属连有：when,while,as,whenever,before,after,since,till,until,assoonas,once,hardly…when,nosooner…than等引导。如：1、时间状语从句引导时间状语从句的从属连词有：when,while,as,whenever,before,after,since,till,until,assoonas,once,hardly…when,nosooner…than等引导。如：Whenhewasstillayoungman,hewasforcedtoleavehishomelandforpoliticalreasons.Ithasbeen15yearssinceheleft.I’lltellhimthenewsassoonasIseehim.Onceyouhavegotusedtoit,youwilllikeit.Iwaitedtillhehadfinishedhiswork.注意：（1）when,as,whilewhen即可引导持续性动作，又可引导短暂性动作。它可以表示主句的动作和从句的动作同时发生，或从句的动作发生在主句动作之前。如：as引导持续性动作，侧重主句和从句的动作同时发生。Hehurriedhome,lookingbehindashewent.Isawyoursisterasshewasgettingonthebusyesterday.Hesangashewalked.as也可表示“随着”，但要注意与with的区别：as是连词接句子。with是介词，接词或词组。Asthedaywenton,theweathergotevencold.(从句，故用谓语动词）Withthedaygoingon,theweathergotevencold.(介词，故用非谓语）While：指的是“在某一时间里”，“在……期间”，从句里的动作必须是持续性的，它也强调主句和从句动作的同时发生，往往侧重主句和从句动作的对比。如：WhilehewasinLondon,hestudiedmusic.WhilewewerewatchingTV,hewaswritingacomposition.while也可做并列连词，表示对照的含义，意思为“然而”。如：Heistallwhilehisbrotherisshort.当when,as,while表示“在…一段时间里”，主从句的动作同时发生时，可以换用。如：While(When或As)wewerediscussing,Mr.Smithcamein.（2）如果when和before引导的从句位于主句之后，有时不能译成“当…时候”和“在…之前”，而要译成“就”、“才”、“这时”等。如：ThestrugglelastedfouryearsbeforetheNorthwonintheend.Healmostknockedmedownbeforehesawme.Shehadnotbeenmarriedmanyweekswhenthemansawherandwasstruckbyherbeauty.IwaswalkinginthestreetwhenIsawhim.before的句型：Itwon’tbelongbeforesb.doessth.不用多久某人就会……Itwillbelongbeforesb.does要过很久某人才会……Itwaslongbeforesb.didsth.过很久某人才做……Itwillbe+一段时间+beforesb.does某人要过多长时间才做Itwas+一段时间+beforesb.didsth.某人过了多长时间才做(3)bythetime,eachtime,everytime,immediately,themoment,theinstant,theminute,soonafter,shortlyafter都可以作为连词，引导时间状语。如：Bythetimehewasfourteen,hehadtaughthimselfadvancedmathematics.bythetime+现在时，主句用将来完成时．例如：Bythetimehearrives,wewillalreadyhaveleftCalifornia.bythetime+一般过去时，主句用过去完成时．例如：Bythetimehearrived,wehadalreadyleftCalifornia.Eachtimehecame,hewouldcallonme.Youmustshowhiminimmediatelyhecomes.IrecognizedhimthemomentIsawhim.(4)till和until①如果主句谓语动词是持续动词，通常用肯定式的主句，表示“直到…为止”。如：Iworkedtill(until)hecameback.②如果主句谓语动词是瞬间动词，则用否定式的主句表示“直到…才，如：Ididn’tgotobeduntil(till)hecameback③放在句首表示强调时一般用until。如：Untilhereturns,nothingcanbedone.注意：–Notuntilhismothercalleddidhegetup.(不倒装为Ｈedidn’tgetupuntilhismothercalled.)Itwasnotuntilhismothercalledthathegotup.(notuntil的强调结构为itis/wasnotuntil…that…)(5)用nosooner…than和hardly…when引导的从句表示“刚……就……”，主句中的动词一般用过去完成时，从句用过去时若把nosooner,hardly提到句首，主句倒装例如：Hehadnosoonergottothelabthanhesetouttodotheexperiment.该句倒装为：Nosoonerhadhegottothelabthanhesetouttodotheexperiment.（5）时间状语从句中谓语动词不能用任何一种将来时，只能用现在时和过去时表示将来时。2、地点状语从句:通常由连词where和wherever等引导。如：Gobackwhereyoucamefrom.Whereveryougo,youmustwritetoyourparents.Wherethereisawill,thereisaway.Wherethereistoomuch,thepoisonandwastemaydogreatharmtothethingsaroundus.注意：不要和where引导的定语从句相混淆．例如：Weshallgowhereworkingconditionsaredifficult.Weshallgototheplacewhereworkingconditionsaredifficult.(状语从句)(定语从句)3、原因状语从句:通常由连词：because,as,since,nowthat引导。区别是:because：表示“因为”，直接而明确的原因和理由，语气最强，why提问的句子，一般都用because回答。Hedidn’tcomebecausehewasill.注意：①在强调句中强调原因状语从句，只能用because引导，不可用as或since，如：Itwasbecausehewasillthathedidn’tgowithus.②because可以引导表语从句，而as,since不可以，但仅用于以下句型:This/That/Itisbecause……It’sbecauseheistoolazy.since：表示“既然”，语气比because弱。Sinceyouarehere,youmustdoit.as：表示“因为”语气比because轻，引导从句可放主句前也可放主句后。Youneedn’tgowithme,asyouarebusy.AsIwasafraid,Ihidmyself.nowthat意思与since相似，表示“既然”。NowthatyouareinHighSchool,youwillprobablyspendmoreinreading.Nowthatalltheguestshavearrived,let’shaveourdinner.③for也表示“因为”，但是并列连词，它连接的不是状语从句，语气比较强。For引导从句不说明主句发生的直接原因，只是提供一些补充说明，且不位于句首．Itmustbemorning,forthebirdsaresinging.seeingthat(既然)和inthat(因为)Seeingthattheweatherisbad,we’llstayathome.Ilikethecity,butIlikethecountrybetterinthatIhavemorefriendsinthecountry.4、目的状语从句:通常由that,sothat,inorderthat,so…that,lest(以免，以防）,incase（以防、免得），forfearthat(以免）等引导：Hegotupearlyinorderthathecouldcatchtheearlybus.Shemarriedhimsothatshemighttendandcomforthim.Iexplainedagainandagainincaseheshouldmisunderstandme.lest，incase,forfearthat后面常用虚拟语气，也就是说其引导的状语从句常用“(should)+动词原形”。例如：Ihidthebooklest(=forfearthat)heshouldseeit.※目的状语从句中谓语动词常含有may(might),can(could)should,will等情态动词。5、结果状语从句:由that,sothat,so…that,such…that引导：Itwasverycold,sothattheriverfroze.Thebookissowrittenthatitgivesaquitewrongideaofthefacts.Thereweresomanypeople(=suchalotofpeople)intheroomthatwecouldnotgetin.Hemadesuchanexcellentspeechthateveryoneadmiredhim.注意：sothat既可引导目的状语从句，又可引导结果状语从句，其区别在于：引导结果状语从句时通常用逗号同主句分开．Hemadeawrongdecision,sothathalfofhislifetimewaswasted.(结果状语从句)Theystartedearlysothattheymightarriveintime.(目的状语从句)6、条件状语从句:由if,unless,aslongas(=solongas)(只要),incase(that)(如果，万一),suppose(that),supposing(that),given(that)(在……的情况下,假定),grantedthat(就算),onconditionthat,providedthat,providingthat等引导：例如：IshallnotgotothecinemaunlessIfinishmyhomeworkbeforeeight.Youmaygoswimmingonconditionthatyoudon’tswimtoofarawayfromtheriverbank.Aslongasyoukeepontryi