大连市第二十四中学　胡颖

语气是动词的一种形式，它表示说话人对某一行为或事情的看法和态度。英语中的虚拟语气表示动作或状态不是客观存在的事实，而是说话人的主观愿望、假设或推测等。比如：If I were you，I would study English harder.现将虚拟语气用法做简要的总结和归纳。

一、虚拟语气在条件从句的用法

条件句有两类，一类是真实条件句；一类是非真实条件句，也就是虚拟条件句。如果假设的情况是有可能发生的，就是真实条件句，谓语要用陈述语气。如If it doesn't rain tomorrow，we will go to the park.如果假设的情况是过去或现在都不存在的，或将来不大可能发生的，则是虚拟条件句。如If he had seen you yesterday，he would have asked you about it.在含有虚拟条件句的复合句中，主句和从句的谓语动词都要用虚拟语气，列表如下：

从句（条件句）　主句（结果句）与现在事实相反的假设动词过去式be一般用were would should+动词原形could might与过去事实相反的假设had+过去分词would should+have+过去分词could might与将来事实相反的假设动词过去式should+动词原形were to+动词原形would should+动词原形could might

与现在事实相反：

If I knew his exact address，I would take the parcel to him without hesitation.

与过去事实相反：

If he had followed the professor's advice，he would have got his doctor's degree in physics.

与将来事实相反的假设从句形式较多，举例说明如下 ：

Ifitweretosnowtomorrow，thepicnic would be canceled.

If it should snow tomorrow，the picnic would be canceled.

If it snowed tomorrow，the picnic would be canceled.

虚拟语气在条件句中使用时应注意以下4种特殊情况：

1.如果从句中含有助动词had/should/were，可以省略if，把助动词移到从句的句首采用局部倒装语序：

Were it to snow tomorrow，our picnic would be canceled.

Should it snow tomorrow，our picnic would be canceled.

Had it not been for the snow，we would have had a picnic.

2.错综时态的条件句

有时条件从句的动作和主句动作发生的时间不一致，这时需要根据具体语境采用表示不同时间的动词形式。

If she had taken the doctor's advice，she might be all right now.

If I were you，I would have chosen a different profession.

3.含蓄条件句

有时候假设的情况并不用条件从句表示出来，而是通过介词短语来表示。……