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1、GrammarandusageUnrealconditionals虚拟语气中的非真实条件句虚拟语气可用于条件句和其它一些从句中。虚拟语气用于条件句中比较多,情况也比较复杂,所以要特别加以注意,首先要判断一下是否应该用虚拟语气,因为条件句分为两种,一种是真实条件句,一虚拟语气的介绍:种是非真实条件句,只有在非真实条件句中才用虚拟语气,在真实条件句中,要用陈述语气。非真实条件句的时态表达:如果假设的情况完全不存在或者实现的可能性很小,可以说几乎没有时,就需要用虚拟语气来表达,也就是说,这时的条件句是非真实的条件句。此时的句子时态比真实条件句中的时态后退一
2、步。虚拟语气1.条件从句和主句中的虚拟语气时间料从句主句与现在事实相反If+主语+动词的过去式(be-were)…主语+should/would/could/might+动词原形与过去事实相反If+主语+had+过去分词主语+should/would/could/might+have+过去分词与将来事实相反If+主语+wereto/(should)+动词原形主语+should/would/could/might+动词原形注:当从句的if省略时,句子要倒装,如IfIwereyou,Iwouldnotdothat.WereIyou,Iwouldnotdo
3、that.注意:在ifI/he/she/it之后,可用were代替was。两者在意义上没有区别,但是were更为正式,特别是在称述心存怀疑的事情时:Ifshewereready,wewouldgo.在与将来事实相反的条件从句中,我们可以用wereto或should+do来表示,如:IfIweretofailmyEnglishtest,Iwouldhavetotakeitagainattheendoftheterm.注意:Ifheshouldcometomorrow,Iwouldtalktohimaboutit.PracticeReadthedialo
4、gueatpage40andfillineachblankwiththecorrectformoftheverbinbrackets.在非真实条件句中,如果有were,had,should,我们可以将if省略,把这些词置于句首,采用倒装形式,如:虚拟条件句中的省略与倒装IfIshouldmeether,Iwouldtellher.=ShouldImeether,Iwouldtellher.IfIwereinyourposition,Iwoulddoitbetter.=WereIinyourposition,Iwoulddoitbetter.Ifthe
5、yhadmadepreparations,theywouldhavesucceeded.=Hadtheymadepreparations,theywouldhavesucceeded.有时非真实条件句中,主句谓语动词所表示的动作和条件从句中谓语动词所表示的动作并不同时发生,这时动词的形式并不完全按照上述表格来进行,而需要按照各自的时间来调整,这样的句子就叫错综时间条件句。错综时间条件句如:Ifyouhadfollowedthedoctor’sadvice,thenyouwouldbeallrightnow.IfIhadn’tfinishedmycom
6、positionbynow,Iwouldbeworkingonittomorrow.Ifshehadpreparedwellforherlessonsyesterday,shewouldn’thavesomanydifficultiesnow.有时一个假设的情况并不用条件从句表示,而用其它方式来表示,这样的句子叫含蓄条件句。用with,without等介词短语或分词短语或者独立主格结构来代替条件从句。含蓄条件句Wemighthavediedwithoutyourhelp.=Wemighthavediedifyouhadn’thelpedus.Havi
7、ngknownintime,wecouldhavestoppedit.=Ifwehadknownintime,wecouldstoppedit.在条件从句中除最常见的连词之外,尚有下列连词:otherwise;incase;butthat;onconditionthat;unless;suppose/supposing(that);solongas;provided/providing(that)2.用相当于if的其他连词表示虚拟结构Iwasbusylastweek,otherwiseIwouldhavecometoseeyou.Butthatyou
8、hadofferedhelp,theycouldn’thavefinishedtheirworkontime
