条件状语从句(一)if引导的条件状语从句getupearlywillgettoschoolontimeIfyougetupearly,youwillgettoschoolontime.Youwillgettoschoolontimeifyougetupearly.feelnervouswillfalloffthestringIfyoufeelnervous,youwillfalloffthestring.Youwillfalloffthestringifyoufeelnervous.pullhertailwilleatyou.Ifyoupullhertail,itwilleatyou.Itwilleatyouifyoupullhertail.berichwillloveyouIfyouarerich,Iwillloveyou.Iwillloveyouifyouarerich.if引导的条件状语从句•一、引导条件状语从句最常用的连词是if,常见的if条件状语从句表示在某条件下,某事很可能发生。条件是可能存在的,主句中某种情况发生的概率也是很高的。•二、主从句的位置•从句可以位于主句前,也可以位于主句后。不过从句在前时,主从句之间必须用逗号隔开。•三、时态•主句用一般将来时,从句要用一般现在时。简称:主将从现。•四、if引导的条件状语从句的用法:•if条件句不一般,几个要点记心间;•条件句,放在前,逗号要放句中间。•条件句表可能,要用一般现在时,主句多用将来时。Exercises•1.如果你再努力些,你将会通过考试。•Ifyou_____(work)harder,you_________(pass)theexams.•2.如果你请他帮忙,他将会帮助你。•Ifyou_____(ask)him,he________(help)you.•3.如果明天下雨,我们就不去公园。•We________(notgo)totheparkifit_____(rain)tomorrow.workwillpassaskwillhelpwon'tgorains•4.如果明天不下雨,我们就去公园。•We_______(go)totheparkifit________(notrain)tomorrow.•5.如果UFO降落在我面前,我将走进去看看有没有外星人。•IfaUFO______(land)infrontofme,I_______(go)intoittolookforaliens.•注:完成课本P38练习2willgodoesn'trainlandswillgoif条件状语从句的其他用法•1.if从句用一般现在时,主句用情态动词(may/might/can/must/should)。•1如果雪停了,我们就可以出去。•Ifitstopssnowing,wecangoout.•2如果你想减肥,你必须少吃面包。•Ifyouwanttoloseweight,youmusteatlessbread.•2.if从句用一般现在时,主句用祈使句。•1如果你想打开录音机,摁蓝色按钮。•Ifyouwanttoturnontherecorder,pressthebluebutton.•2如果红色的灯不亮,请等待三十秒钟。•Iftheredlightdoesn'tcomeon,pleasewaitforthirtyseconds.•注:完成课本P30练习1、2•3.if从句用一般现在时,主句用一般现在时。•如果把冰加热,它就会化成水。•Ifyouheatice,itturnstowater.•(也可用willturn)•注:条件句表事实,主句常用现在时。•4.if从句用现在进行时,主句用一般将来时。•如果你是在找彼得,上楼就会找到他。•IfyouarelookingforPeter,youwillfindhimupstairs.•5.if从句用现在完成时,主句用一般将来时。•如果你吃完了,我就叫服务生来算账。•Ifyouhavefinisheddinner,Iwillaskthewaiterforthebill.类似于if的条件状语从句的引导词•unless(除非;如果不)•aslongas(除非;只要)•Supposing(假设)•onconditionthat(条件是)•incase(如果)•Youcan'tlearnEnglishwellunlessyouworkhard.•除非你努力学习,否则你学不好英语。•YoucanusemybikeonconditionthatyoureturnitbyFriday.•你可以使用我的自行车,条件是你星期五以前还。•Aslongasyoudrivecarefully,youwillbeverysafe.•只要你开车小心,你就会很安全。•Supposingitrains,whatwillyoudo?•如果下雨你怎么办呢?•Incaseshecomesback,letmeknowimmediately.•假使她回来了,立刻告诉我。条件状语从句的时态•表解:主句从句1一般现在时一般现在时2祈使句3一般将来时4过去的某一态时过去时某一态时