条件状语从句

条件状语从句

ConditionClauseIf…Unless…Aslongas…onconditionthat……if如果1.1if后面的时态问题真实条件Ifitrainstomorrow,thegamewillbepostponed.非真实条件（虚拟条件句）*IfIwereyou,Iwouldseizetheopportunity.*Ifthestudenthaddoneproperrevision(复习),hewouldnothavefailedthetest.1.2.特殊用法

1.2.1evenif转折+假设条件(usedtoemphasizethat,althoughsomethingmayhappenormaybetrue,itwillnotchangeasituation)Evenifshesurvives,she’llneverfullyrecover.Themedicalteammembersaredeterminedtorescuepeopleindisease-strickenareas,evenifitmeansthembeinginfected.

1.2.2if和形式宾语连用（主句动词包含喜怒）Shewon’tlikeitifyouarrivelate.IwouldappreciateitifyoucouldlendmeyourE-dictionary.Iwouldpreferitifyoudidn’tsmokeinhere.HehatesitifpeoplecallhimFatty.1.2.3if从句的简化1)ifitispossible/necessary=ifpossible/necessaryTastethesoupandaddsaltandpepperifnecessary.Iwanttogetbackbyfiveo’clockifpossible.

2)ifso&ifnotifsoHemaybebusy;ifso,Iwillcalllater.(ifso=ifheisbusy)ifnotIftheadmissionisfree,Iwillgo.Notifnot.(ifnot=iftheadmissionisnotfree)*3)ifnot(usedwhenyouareaddingthatsomethingmaybeevenmore,less,better,worseetc.thanyouhavejustsaid)Johnrunsasfastas,ifnotfaster,thanJack.Thesnowwasnowtwofeetdeep,makingitdifficult,ifnotimpossible,togetthecarout.Theirpolicieshavechangedlittle,ifatall,sincethelastelection.1.3Whatif…? (如果…那会怎样？)Whatif…=Whatwillhappenif…?“Whatifitrainstomorrow?”“We’llhavetopostponeit.”1.4ifonly(要是…就好了)Youuseifonlytoexpressawishordesire,especiallyonethatcannotbefulfilled.Ifonlyyouhadtoldmethatsometimeago.Ifonlyitwerethatsimple!'Hey,listentome,allthatnonsenseisover.'—'Ifonly,Timothy,ifonly.‘1.5usedwhenyouwanttomakeapoliterequestorremark:WouldyoumindifIopen/opened(=canIopen)thewindow?Ifyou'dliketotakeaseat,Mr.Changwillbewithyouinamoment.*1.6Wesometimesuseshouldinhypotheticalconditionalclauseswithiftoexpresspossibility.Itisformal:IfyoushouldwishtousetheInternet,thereisacodeavailableatthereceptiondesk.Ifyoushoulddecidenottogoonthetrip,youwillgetafullrefund.ShouldyouwishtousetheInternet,thereisacodeavailableatthereceptiondesk.Shouldyoudecidenottogoonthetrip,youwillgetafullrefund.2.unlessUnlessthegovernmentchangesitspolicy,theeconomywillgetworse.=Ifthegovernmentdoesnotchangeitspolicy,…Thechildwon’tgotosleepunlessyoutellhimastory.=…ifyoudonottellhimastory.注意点1：和until不同，unless只能是连词，其后不加doingsth/beingdoneYoushouldremainsilentunless_youareasked__(ask)tospeak.Thechildwon’tgotosleepunless_youtell_(tell)astory.注意点2：unless后面符合“从现”的规则，不接将来时，但可以接现在完成时。Unlesssomeextramoneyisfound,thetheatrewillclose.Iwon’tchangeanythingunlesssomeonehasaskedmeto.表达过去的事情时，也可用过去式：Theythreatenedtokillhimunlesshegavethemthemoney.3.as/solongas:只要Aslongaswekeepplayingwell,we’llkeepwinninggames.Youcangoouttoplayaslongasyoustayinthebackyard.*注意点：aslongas还可以表示“为了能长久…”，前面一般会出现forYoucanstayforaslongasyouwant.Shetriedtostayawakeforaslongasshecould.

4.onconditionthat(=onlyifaparticularthingisagreedto)只要（同意一件事）（前提条件）Thepolicereleasedhimonconditionthathereturnthefollowingweek.Hespoketoreportersonconditionthathewasnotidentified.5.provided(that)…（前提条件）Ifyousaythatsomethingwillhappenprovidedorprovidedthatsomethingelsehappens,youmeanthatthefirstthingwillhappenonlyifthesecondthingalsohappens.Thisnewfilmwillattractthecrowds,providedthatitgetsplayedupintherightway.Iwillagreetogoprovided(that)myexpensesarepaid.

6.suppose/supposingthat…Suppose/Supposing(that)wemissthetrain,whatshallwedo?Look,supposeyoulostyourj