省略連詞if 采用倒裝的非真實(shí)條件句
　　在書面語中，條件從句可以不用連詞if, 而將謂語中的過去式were,had或should等移至主語之前，構(gòu)成倒裝。
　　例：Were you in my position, you would do the same.
　　假如你處在我的地位，你也會(huì)這樣干的。
　　例：Had he come earlier, he would have met her.
　　要是他早點(diǎn)來的話，他就會(huì)見到她了。
　　虛擬語氣在儲(chǔ)蓄條件句中的應(yīng)用
　　非真實(shí)條件句中的條件從句有時(shí)不表示出來，只暗含在短語或上下文中，這種句子叫做儲(chǔ)蓄條件句。常見的有but,for ,without等引導(dǎo)的短語，以及or, or else, otherwise, but 等后面的分句。
　　例：But for your help we couldn’t have succeeded in the experiment.
　　如果沒有你的幫助，我們的實(shí)驗(yàn)室是不會(huì)成功的。
　　例：We could have done better under more favourable conditions.
　　在更有利的條件下，我們能夠做得更好些。
　　經(jīng)典考點(diǎn)：
　　1、____right now, she would get there on Sunday.
　　A)Would she leave
　　B)If she leaves
　　C)Were she to leave
　　D)If she had left
　　2、____for my illness I would have lent him a helping hand.
　　A)Not being
　　B)Had it not been
　　C)Without being
　　D)Not having been
　　3、We didn’t know his telephone number, otherwise we ____him.
　　A)would have telephoned
　　B)must have telephoned
　　C)would telephone
　　D)had telephoned
　　4、A safety analysis____the target as a potential dandger Unfortunately, it was never done.
　　A)would identify
　　B)will identify
　　C)would have identified
　　D)will have identified
　　解析：
　　1、答案選C。從句子結(jié)構(gòu)可知，本題是表示與將來事實(shí)相反的虛擬語氣。主句的謂語是“should+動(dòng)詞原形”。同時(shí)，從句省略了連詞if, 可以將were提前，構(gòu)成倒裝。只以C符合語法規(guī)則。本題意思：如果她馬上動(dòng)身的話，她可能在星期天到達(dá)那里。
　　2、選B。從句子結(jié)構(gòu)可知，空缺處應(yīng)填入表示與過去事實(shí)相反的虛擬條件從句，并且將連詞if 省略。此時(shí)應(yīng)把虛擬語氣的謂語動(dòng)詞提前。符合語法規(guī)則的只有B項(xiàng)。
　　3、選A。本題中otherwise引出的是一種與事實(shí)相反的假設(shè)條件，后面的句子應(yīng)用虛擬語氣。前一分句暗示了一個(gè)過去的時(shí)間，所以用不著would have done的形式，相當(dāng)于If we had known his telephone number, we would have telephoned him.
　　4、選C。根據(jù)unfortunately后面直接陳述一個(gè)過去的事實(shí)，可以推斷出第一個(gè)句子里含有一種“應(yīng)該做某事而沒有做的”虛擬條件。C項(xiàng)用于表示與過去事實(shí)相反的虛擬語氣，正合題意。B、D不是虛擬語氣。

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