if条件状语从句和宾语从句

Revision,AdverbialClauseofConditionif引导的条件状语从句&宾语从句,-复习课,Sheisdoingherhomework.,Ifyouarehard-working,youwillgetgoodgrades.,Shegetsgoodgrades.,Ifyouplaycomputergamesonweekdays,youllbeverytiredinclass,yourparentswillbesad.,youwontgetgoodgrades.,youreyeswillbepoor,1)条件状语从句通常由if或unless(=ifnot)引导，从句中常用一般时代替将来时，即if或unless后的句子谓语用一般现在时。但是，主句则通常用将来时，情态动词或祈使句。,时态主将从现主句一般将来时，从句一般现在时,1.如果主句是一般将来时，从句则用一般现在时。Ifitrains（从句），Iwillstayathome.Illgowithyouifyoudontwanttogoalone（从句）.2.如果主句含有must,may,can等情态动词，从句也要用一般现在时。Ifyoudrivetoofast,youmayhaveanaccident.Youmuststopifthetrafficlightisred.3.如果主句是祈使句，从句同样要用一般现在时。Dontgoandplayfootballifyoudontfinishyourhomework.PleasecallmeifhecomesnextSunday.,if条件状语从句结构及时态,Revision,If引导条状语从句时，从句中用一般现在时代替一般将来时。,1.Ifhe_(go)tothemovies,hewontfinishhiswork.,goes,2.IfI_(become)adoctor,Icanhelpothers.,become,3.Ifwe_(have)time,wewillgototheparktomorrow.,have,4.如果你去，我也去。,Ifyougo,Iwillgo.,5.如果明天下雨，请带雨衣。raincoat,Pleasetakearaincoatifitrains.,excellent,Ifyouarefreethisweekend,whatwillyoudo?,IfIamfree,sleepwatchTVplaycomputergames,practice,Ifyouwanttogetgoodmarks,dowhat?Dontdowhat?,Ifyouwanttogetgoodmarks,_.Ifyouwanttogetgoodmarks,dont_.,studyhardlistentoteacherscarefully.dohomeworkbyyourself.,copyyourhomework.talkintheclasscheatintheexams,If条件句的替代形式：（1）祈使句+and/or+陈述句（谓语动词通常用将来时态）。其中，and表示句意顺承；or表示转折，意为“否则”。e.g.Ifyouworkhard,youllpasstheexameasily.=Workhard,andyoullpasstheexameasily.Ifyoudontworkhard,youllfallbehindothers.=Workhard,oryoullfallbehindothers.,verygood,（2）用介词with,without的替代形式：e.g.Ifthereisnowater,thefishmaydie.=Fishmaydiewithoutwater.Ifyouhelpme,Illfinishmytaskontime.=Withyourhelp,Illfinishmytaskontime.,if引导的条件状语从句和if引导的宾语从句的区分:,If在宾语从句中翻译为“是否”If在条件状语从句中翻译为“如果”,IllgotoseeyouifIamfreenextweek.,Iwanttoknowifheisateacher.,whether,1.if在句中的含义不同,2.if在从句中的位置不同,If引导的宾语从句放在主句之后；而if引导的状语从句可放在主句之前也可放在主句之后,=Ifitdoesntrain,Iwillgoouttomorrow.,Iwillgoouttomorrowifitdoesntrain.,Idontknowifthetrainhasarrived.,If引导的条件状语从句放于句首时多用逗号隔开；而if引导的宾语从句则不能。,3.时态要求上有区别,If引导条件状语从句的时态为一般现在时记住“主将从现”,1.Iwanttoknowifthereasportsmeetingnextmonth.,doesntrain,willbe,2.Ifitdoesntrain,wellgoout,If引导的宾语从句的时态由主句及本身时态决定；,找出下列句子中哪些是if条件状语从句，哪些是if宾语从句,1.Canyoutellmeifshecancometothemeeting?2.Shewillnotgothereifitisrainytomorrow.3.Icantguessifshewillbeangry.4.Ifwehelpeachother,wewillgetgoodresults.,If引导的条件状语从句或宾语从句的练习,1IfI_(notunderstand）,Iwillaskmyteacherforhelp.IfI_(copy)yourhomework,Iwillcheatmyself.Idontknowifit_(rain)tomorrow.MyteacheraskedmeifI_(finish)myhomeworkalready.,dontunderstand,copy,willrain,hadfinished,summary,if的用法,2.引导条件状语从句：译为“如果，假如”(1)if从句+祈使句(2)if从句+主句（一般将来时）(3)if从句