条件If 从句谓语形式 主句谓语形式过去现在未来过去时 (were)would/could/should/might +V. ( 原 )壹.虚拟语气在条件状语从句中的用法。过去完成时would/could/should/might + have+ p.p.1. 过去时2.should+V.3. were to dowould/could/ should/ might +V. ( 原 ) 二、主句与从句的动作发生在不同的时间 , 这时主从句位于动词的虚拟语气形式因时间不同而不同 , 这叫做混合条件句。 例句中从句与过去事实相反 , 主句与现在事实相反 If you had asked him yesterday, you would know what to do now.三 . 虚拟语气在宾语从句中的用法1. 在动词 wish 后的宾语从句中 , 表示与现在或过去的事实相反 , 或对将来的主观愿望 , 从句通常省略连词 that 。I wish every dayI wish every day werewere my birthday.my birthday.1) 表示对现在情况的虚拟 : 从句动词用过去式或过去进行式 (be 动词一般用were) 。• 2) 表示对过去情况的虚拟 : 从句动词常用“ had ＋过去分词”。• I wish/wished I hadn’t eaten so much watermelon.四、 as if/as though 引导的条件句由 as if (as though) 或 even if (even though) 引导的状语从句表示比较或方式时 , 从句谓语形式为动词的过去式(be 用 were) 或 “ had ＋过去分词”。He treats me as if I were a stranger.五、 It is (high) time 等从句中 表示“该做而没有作的事情”，动词用一般过去时。 如： It’s high time we began to work. I would rather you came tomorrow. 六、表示“建议、要求、命令”意义的各种从句中 advise advise ，， suggestsuggest ，， proposepropose ，， insist insist ，， requestrequest ，， recommendrecommend ，， demand demand ，， require require ，， urgeurge ，， intend intend ，， order order ，， commandcommand 这些词从句谓语用虚拟语气 should do ， should 可省略。 He insisted that John do this job.七、省掉 if, 从句倒装 If you had come yesterday, you would have met him. If it were to rain tomorrow,we wouldn’t go there.Had you come yesterday, you would have met him.Were it to rain tomorrow,we wouldn’...
