关于虚拟语气的详细讲解

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一、概念 [Subjunctive Mood] 中文译作＂虚拟语气＂。它是一种动词形式，表示说话人的某种假设、愿望、怀疑、猜测、建议等含义。

二、语法结构 1.if结构（非真实条件句——表示的是假设的或实际可能性不大的情况）与..事实相反 If从句主句过去 Had done Would* have done 现在 Were/did Would* do 将来 Should do/were/were to do Would* do 例句：If there hadn't been much rain in spring, we would have had a good harvest now. [过去] If he smoked less, his cough might be well soon. [现在] If the lecturer should be late, you would have to make a speech first. [将来] 备注：

（1）上表中'*'，would都可转换为should、could、might。

(2) 如果为时间错综句的话，左右两栏可互相搭配，排列组合。例句： He would still be alive today if he hadn't taken that drug. [与现在事实相反] [与过去事实相反]

（3） if可转换为其他形式例句：Without your advice, our meeting wouldn't have been so successfully. [过去] （=>可转换为：If there hadn't been your advice, we …） Your notes are almost illegible （难以辨认的）. Notes typed out would be a lot easier to read. [将来] （=>可转换为：If the notes had been typed out, it would be a lot easier to read.） I should have gone to see Dr. Smith and he might have cured me of the disease.[过去] （=>可转换为：If he have gone to see Dr. Smith, he ..）

2、wish结构与..事实相反过去 Had done 现在 Were/did 将来 Would 备注：可转换为其他形式。

例句：He talks as if （好像） he had done all the work himself. [过去] I wish I were a bird. I wish he handn' done that. I wish I would be rich in the future.

3、should结构从句中用“should + 动词原形”构成。而且should可以省去。用于此结构的动词有：advise, direct, agree, ask, demand, decide, desire, insist, order, prefer, propose, request, suggest,intend等。例句：The teacher suggest he (should) read English aloud. 注意：当insist表示“坚持认为”、suggest表示“表明，显示”时，不用虚拟语气。

例句：The look on his face suggested that he was quite satisfied with what I had done for him. He insisted that he was honest.

4、would rather +从句在这种结构中，从句的谓语动词用过去形式表示虚拟。例句：I would rather you did this instead of me.

5、主语从句中的虚拟语气 1)It be + 形容词 + that ...(should)... 用于该句型的形容词是：necessary, good, important, right, wrong, better, natural, proper, funny, strange, surprising . 一些名词也可以用于在该结构中。

如：a pity, no wonder.... 2)It be + 过去分词 + that ...(should).... 用于该结构中的过去分词是表示“建议、请求、命令”等词的过去分词。如：desired, suggested, requested, ordered, proposed等。 3)It is time(about time, high time)that ...（过去式动词形式或should+动词原形）.... It is high time I went home now. = It is high time I should go home now.

6、表语从句、同位语从句中的虚拟语气在suggestion, proposal, order, plan, idea, advice, decision等需要有内涵的名词后面的表语从句、同位语从句中，要使用虚拟语气。

其谓语动词应用：should+原形动词。另外连接从句的that不能省略。例：My suggestion is that we should go there at once. What do you think of his proposal that we should put on a play at the English evening？

三、使用范围及判断

1、虚拟语气表示一种不能实现的假设。该语法主要用于if条件状语从句。也可用于主语从句、表语从句、宾语从句等。

2、if条件状语从句中虚拟语气的判断判断是真实条件句还是非真实条件句。

只有在非真实条件句中才使用虚拟语气。通过句子意思，看假设的条件是否能够实现，能够实现是真实条件句，不能使用虚拟语气；假设的条件不能实现则是非真实条件句，要用虚拟语气。判断这个假设是与哪个事实相反。通常有三种情况：①与过去事实相反。②与现在事实相反。③与将来事实可能相反。

3、“后退一步法” 后退一步法是指在准确地判断了该句与哪一事实相反后，按虚拟语气的后退一步法处理从句谓语动词的时态。

即：在非真实条件状语从句中，谓语动词按正常情况“后退一步”。也就是： 1）与过去事实相反，在从句中用过去完成时形式表示。 2）与现在事实相反，在从句中用过去一般时形式表示。 3）与将来事实可能相反，在从句中用过去将来时形式表示。主句中则用情态动词would, should, could 等加一个与从句一致的动词形式。例：If I had come her yesterday, I would have seen him. If I were a teacher, I would be strict with my students. If it should snow tomorrow, they couldn't go out.

四、注意事项 1.if条件句中如有were, should, had，可以省去if，并使用倒装语序。

2、在现代英语中if条件状与从句中的谓语动词如果是be其过去形式一般用were。

3、wish 后面宾语从句中的虚拟语气，按“后退一步法”处理从句的谓语动词。注意：与哪个事实相反，不能以主句的时态为判断依据，而是根据从句的意义判断。