Unit7语法专项课件条件句unless-沪教版英语八年级上册

教学课件沪教（牛津）英语八年级上册Unit7语法专项——条件句&unless

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学习目标1.掌握零条件句结构与用法（真理/规律）。2.掌握第一条件句结构与用法（将来可能）。3.牢记if从句不用will，用一般现在时表将来。4.理解unless=if…not，会同义句转换。5.能在填空、选择、句型转换中正确运用。零条件句—定义零条件句表示客观真理、自然规律、必然结果。只要条件满足，结果一定发生。适用于科学常识、生活规律。主从句都用一般现在时。不涉及将来，只讲事实。零条件句—结构结构：If+一般现在时，一般现在时从句：If+主语+动词原形/三单主句：主语+动词原形/三单注意：主句主语三单，动词用三单。if可放句首或句中，放句首加逗号。零条件句—例句例句：Ifyoumixblueandyellow,yougetgreen.例句：Ifyoutakeafishoutofwater,itdies.注意：主从句都不用will。注意：三单动词要变化（die→dies）。这是考试最常考的易错点。第一条件句—定义第一条件句表示将来可能发生的事。描述假设条件和将来结果。条件可能成立，也可能不成立。常用于计划、建议、警告。第一条件句—结构结构：If+一般现在时，will+动词原形从句（if）：一般现在时，不用will主句：will+动词原形遵循“主将从现”原则。if可放主句前或后。第一条件句—例句例句：Ifitrainstomorrow,wewillstayathome.例句：Ifyoustudyhard,youwillpasstheexam.注意：if从句一定不用will。注意：主句可以用can/may/must代替will。主将从现—核心规则主将从现：主句用将来时，if从句用一般现在时。if,unless,when,assoonas都遵循此规则。从句用来表将来的条件。错误：Ifitwillrain…正确：Ifitrains…unless—含义与等价unless=if…not，意为“除非；如果不”。表示否定条件。用于同义句改写，是必考考点。unless从句也用一般现在时。不与not连用，本身含否定。unless—结构结构：Unless+一般现在时，主句will…等价：If…not+一般现在时，主句will…例句：Unlessyouhurry,youwillbelate.=Ifyoudon’thurry,youwillbelate.从句一律用一般现在时。unless注意事项1.unless不能和not连用。2.unless从句不用will。3.主语三单，动词用三单。4.可放句首或句中，放句首加逗号。5.改写时时态不变。零条件句vs第一条件句零条件句：真理/规律，主从句都现在时。第一条件句：将来可能，主将从现。判断技巧：看是否将来时间（tomorrow…）。看是否科学事实。基础训练1—零条件句填空1.Ifyouheatwater,it___________(boil).2.Ifyouputsaltintowater,it___________(disappear).3.Ifyoudropaglass,it___________(break).4.Ifyouwateraplant,it___________(grow).boilsdisappearsbreaksgrows基础训练25.Ifit___________(rain)tomorrow,we___________(stay)home.6.Ifyou___________(study)hard,you___________(pass)theexam.7.Ifshe___________(come),I___________(call)you.8.Ifyoudon’trest,youwillbetired.→Unlessyou______,youwillbetired.9.Ifitdoesn’tsnow,wewillgoout.→Unlessit______,wewillgoout.rainswillstaystudywillpasscomeswillcallrestsnows单项选择1.Ifyoumixredandblue,you______purple.A.getB.willgetC.got2.Ifyou______hard,youwilllearnEnglishwell.A.studyB.willstudyC.studied3.Unlessyou______early,youwillmissthebus.A.leaveB.willleaveC.left4.Ifit______tomorrow,wewillgotothezoo.A.notrainB.doesn’trainC.won’trainAAAB单项选择5.Ifyouputwoodintowater,it______.A.floatB.floatsC.willfloat6.Iwon’tgoout______itissunny.A.ifB.unlessC.when7.Whatwillyoudoifit______sunnytomorrow?A.isB.willbeC.was8.Unlesshe______hard,hewon’twin.A.triesB.willtryC.triedBBAA用所给词适当形式填空1.Ifyoucoolwater,it____________(become)ice.2.Ifyou_________(eat)toomuch,you__________(get)fat.3.Unlessyou_______(wear)warmclothes,you_________(catch)acold.4.Ifhe_____________(nothurry),he__________(miss)thetrain.5.Ifyou___________(notwater)theflower,it_________(die).6.Unlesswe__________(start)now,we__________(be)late.becomeseatwillgetwearwillcatchdoesn’thurrywillmissdon’twaterwilldiestartwillbe句型转换（同义句）1.Ifyoudon’tstudyhard,youwon’tpass.→________________________________________2.Ifitdoesn’traintomorrow,wewillhaveapicnic.→________________________________________3.Unlessyoureadmore,youwon’timprove.→________________________________________4.Unlessshegetsupearly,shewillbelate.→________________________________________Unlessyoustudyhard,youwon’tpass.Unlessitrainstomorrow,wewillhaveapicnic.Ifyoudon’treadmore,youwon’timprove.Ifshedoesn’tgetupearly,shewillbelate.完成句子1.如果你把鱼拿出水，它就会死。Ifyoutakeafishoutofwater,it__________.2.如果明天不下雨，我们就去公园。Ifit____________________tomorrow,wewillgotothepark.3.除非你早睡，否则你会犯困。__________yougotobedearly,youwillfeelsleepy.diesdoesn’trainUnless4.如果你努力，你就会成功。__________youworkhard,youwillsucceed.5.如果你把冰放进热水，它会融化。Ifyouputiceintohotwater,it__________.6.除非你现在走，否则你会迟到。Unlessyou__________now,youwillbelate.Ifmeltsleave高频易错点总结1.零条件句：主从句都用一般现在时。2.第一条件句：主将从现。3.if/unless从句一定不用will。4.unless=if…not，不再加not。5.三单动词必须正确变化。课堂总结（一）零条件句：If+一般现在时，一般现在时用于真理、规律、必然结果。无将来含义，主从句时态一致。课堂总结（二）第一条件句：If+一般现在时，will+原形遵循主将