英语的动词有三种语气形式

　英语的动词有三种语气形式，即陈述语气、和。陈述语气用来说明事实或就事实提出询问，可用于陈述句、疑问句和某些感叹句中；祈使语气用于表示请求、命令、建议或警告等。

虚拟语气是谓语动词的一种特殊形式，用来表达假设、主观愿望、猜测、建议、可能或空想等非真实情况。如：

He is honest. 他很诚实。（陈述语气）

Don‘t be late next time. 下次别迟到。（祈使语气）

If I were you ，I would not go. 我要是你，我就不会去。（虚拟语气）

I wish I had a lot of money. 要是我有很多很多钱就好了。（虚拟语气）

第一类

虚拟语气在条件句中的用法：

条件句有真实条件句和虚拟条件句两种。真实条件句所表示的假设是有可能发生的，此时主句不用虚拟语气；而虚拟条件句则表示一种假想，与事实相反或不大可能会发生，此时用虚拟语气。如：

If I have time，I will go. 假若我有时间，我就去。（陈述语气）If I were you，I would go. 假若我是你，我就去。（虚拟语气）

If you tried again，you might succeed. 要是你再试一试，你可能会成功的。(might表可能)

If you tried again ，you could succeed. 要是你再试一试，你就能成功了。(could表能力)

2、错综时间虚拟条件句即条件从句与主句所指时间不一致，如从句指过去，而主句即指的是现在或将来，此时应根据具体的语境情况，结合上面提到的三种基本类型对时态作相应的调整： If it had rained last night, the ground would be wet now. 要是昨晚下过雨的话，现在地面就会是湿的。

You would be much better now if you had taken my advice. 假若你当时听我的话，你现在就会好多了。

3、If虚拟条件句的否定（含蓄条件句）常考两个句型：If it weren’t for…和If it hadn’t been for…，其意为“若不是(有)” “要不是”。如：

If it weren’t for water, no plant could grow. 要是没有水植物就无法生长。

If it hadn’t been for your assistance ，we wouldn’t have succeeded.

=But for your assistance ，we wouldn’t have succeeded.

=Without your assistance ，we wouldn’t have succeeded.

4、If虚拟条件句的倒装形式，即把were, had, should置于句首。例：

Were I in school again (= If I were in school again), I would work harder.

Had you asked me, I would have told you. (=If you had asked me,…)

第二类

使用虚拟语气的常见结构或从句：

1.*wish与hope接宾语从句的区别在于：hope表示一般可以实现的希望，宾语从句用陈述语气。wish表示很难或不大可能实现的希望,宾语从句用虚拟语气。试比较：

（1）We hope they will come. (We don’t know if they can come.)

（2）We wish they could come. (We know they are not coming.)

2.if only 与I wish一样，也用于表示与事实相反的愿望，其后所虚拟语气的时态与wish后所接时态的情况相同： If only she had had more courage! 她再勇敢一些就好了。

If only I had listened to my parents! 我要是当时听了父母的话就好了。

If only she would go with me! 她要是愿意和我一道去就好了!

*if only 通常独立使用，没有主句。

3.l would rather后句子用虚拟语气只分现在和过去

在would rather, would sooner, would just as soon后的that从句中, 句子谓语习惯上要用虚拟语气，表示"宁愿做什么" ，具体用法为：

①　一般过去时表示现在或将来的愿望

I’d rather you went tomorrow (now). 我宁愿你明天(现在)去。

②　用过去完成时表过去的愿望

I’d rather you hadn’t said it. 我真希望你没有这样说过。

4.l as if (though)从句用虚拟语气

以as if (as though)引导的或表语从句，有时用虚拟语气,则与wish用法相同，例：

He acts as if he knew me. 他显得认识我似的。

They treat me as though I were a stranger. 他们待我如陌生人。

He talks as if he had been abroad. 他说起话来好像曾经出

过国。

注：两点说明

(1) 从句所表示的内容若为事实或可能为事实，也可用陈

述语气：

It looks as if we’ll be late. 我们似乎要迟到了。

(2) 注意It isn’t as if…的翻译：

It isn’t as if he were poor. 他不像穷的样子(或他又不穷)。