1f引导的条件状语从句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。如：Ifyouaskhimhewillhelpyou.如果你请他帮忙，他会帮你的。Ifyoufailintheexam,youwilllethimdown.如果你考试不及格，你会让他失望的。Ifyouhavefinishedthehomework,youcangohome.如果你作业做完了就可以回家了。另外，if从句还表示不可实现的条件或根本不可能存在的条件，也就是一种虚拟的条件或假设。从句多用一般过去时或过去完成时，表示对现在或过去的一种假设。如：IfIwereyou,Iwouldinvitehimtotheparty.如果我是你，我会邀请他参加聚会。IwouldhavearrivedmuchearlierifIhadnotbeencaughtinthetraffic.要不是交通堵塞，我本会来得早一些。另外你还要注意讦条件句的时态搭配1.讦从句用一般现在时，主句用一般将来时Ifherunshe'llgetthereintime.如果他用跑的，他就会及时赶到那儿。Thecatwillscratchyouifyoupullhertail.如果你拉猫的尾巴，它就会抓你。2.if从句用一般现在时，主句用may/might/canIfthefoggetsthickertheplanemay/mightbediverted.如果雾在大一些，飞机可能就会改在别的机场降落。Ifitstopssnowingwecangoout.如果雪停了，我们就可以出去。3.if从句用一般现在时，主句用must/shouldIfyouwanttoloseweightyoumust/shouldeatlessbread.如果你想减肥，你必须少吃面包。4.讦从句用一般现在时，主句用一般现在时Ifyouheatice计turnstowater.（也可用willturn）如果把冰加热，它就会化成水。5.讦从句用现在进行时，主句用一般将来时IfyouarelookingforPeteryou'llfindhimupstairs.如果你是在找彼得，上楼就会找到他6.讦从句用现在完成时，主句用一般将来时2IfyouhavefinisheddinnerI'llaskthewaiterforthebill.如果你吃完了，我就叫服务生来算账If条件状从句练习()1.Ifyoutotheparty,you'llhaveagreattimeA.willgoB.wentC.goD.going()2.-Whatareyougoingtodotomorrow?--We'llgotothelibrarytomorrowifit.A.isn'trainB.rainC.won'trainD.doesn'train()3.Whatwillyoudoifyoutotheoldfolk'shomevisit?A.goB.wentC.goingD.willgo()4.IfIeatfood,I'llbeveryfat.A.toomanyB.manytooC.toomuchD.muchtoo()5.I'llgivethebooktohimifhe__herenextSunday.A.willcomeB.comesC.iscomingD.came()6.Ihertheanswerifshe___me.A.cantell,willaskB.willtell,willasC.wouldtell,askD.willtell,asks7.We'llgotothefarmandhelpthefarmerswiththeapple-pickingifittomorrow.A.won'trainB.willberainyC.doesn'trainD.isn'training8.Thereisgoingtoasportsmeetingnextweek.Ifit,we'llhavetocancelit.A.be,willrainB.have,willrainC.be,rains9.Yourteacherwillbeunhappyifyoutoschoollate.A.comeB.willcomeC.arecomingD.came10.Idon'tknowifhe__.Ifhe__,pleaseletmeknow.A.comes,comesB.willcome,willcomeC.willcome,comesD.comes,willcome二、用所给词的适当形式填空。1.Ifshe(notget)homeontime,hermomwillbeworried.2.IfTomworkshard,he(make)alotofmoney.3.IfIstudyhard,mydream(实现).4.Ifhe(争论)hisfriend,hewillbeverysad.5.Ifyoufightwithyourbrother,what(发生)?36.Callmeifhe(回来).7.Hecanmakegreatprogressifhe(追随，听从)myadvice.()8.IfIfindhisphonenumber,Iyou.A.tellB.toldC.willtellD.havetold()9.I__theCDstoyouifIhavetimetomorrow.A.willreturnB.returnedC.havereturnedD.return()10.ThestudentswillgototheSummerPalaceifittomorrow.A.won'trainB.isn'trainingC.doesn'trainD.isn'train()11.Iwon'twatchtheTVplayifmyfather___medomyhomework.A.letB.willletC.won'tletD.lets()12.Ifyou___quiet,I'lltellyouwhathappened.A.willB.areCaretobeDbe()13.Ifyougototheparty,you___agoodtime.A.wouldhaveB.haveC.willhaveD.had()14.Don'tworry.PeterwillcallyouassoonasheLondon.A.willgettoB.getstoC.gettoD.gotto()15.Hedoesn'ttellmewhenhe.I'lltelephoneyouassoonashe.A.willcome,comesB.will...
