高中英语语法虚拟语气讲解

虚拟语气

概念:

虚拟语气用来表示说话人的主观愿望或假想，所说的是一个条件，不一定是事实，或与事实相反。 条件句可分为两类，一类为真实条件句，一类为非真实条件句。非真实条件句表示的是假设的或实际可能性不大的情况，故采用虚拟语气。

一、

1真实条件句

真实条件句用于陈述语气，假设的情况可能发生，其中 if 是如果的意思。

时态关系

句型：条件从句 主句

一般现在时 shall/will + 动词原形 If he comes, he will bring his violin. 典型例题

The volleyball match will be put off if it ___. A. will rain B. rains C. rained D. is rained 答案B。真实条件句主句为将来时，从句用一般现在时。

注意：1) 在真实条件句中，主句不能用be going to表示将来，该用shall, will.

(错) If you leave now, you are never going to regret it.

(对) If you leave now, you will never regret it.

2)表示真理时，主句谓语动词便不用shall (will) +动词原形，而直接用一般现在时的动词形式。

2.非真实条件句

1）时态：可以表示过去，现在和将来的情况。它的基本特点是从句 时态逆推。

[例句]

①.If they were here now , they would help you .如果他们在这里，他们就会帮助你。

② If you had come earlier , you would have met him.如果来得早些，你就会见到他了。

③. If it should rain , the crops would be saved.如果下雨，庄稼就能得救了。

3. 混合条件句、错综条件句

虚拟条件句中的主句和从句的动作发生在不同的时间，这时主句和从句的谓语动词的形式根据各自发生的时间来表达。

If you had asked him yesterday , you would know what to do now.

如果你昨天问过他，你现在就知道该怎么做了。

4．省略 if 的条件从句

当从句中有 were, had 或 should 时，可省略if ，而把它们放在句首，实行倒装。

①. If they were here now , they would help you .

→Were they here now …

②. If you had come earlier , you would have met him.