3. 表示与将来事实可能相反的假设和结果。如:

If it were Sunday tomorrow, I should / would/could/might go to see my grandmother.

如果明天是星期天，我就 (可能)去看望我奶奶。

　If it were to snow this evening, they would not go out.

　如果今晚下雪，他们将不出去了。

　If it should rain, the crops would be saved.

三、if省略句

在条件句中如果出现were, had, should可省去if，把were, had或 should提至句首，构成倒装句，例如：

Had the doctor come last night, the boy would have saved.

Were I to go to the moon one day, I would see it with my own eyes.

Should it rain tomorrow, we would stay at home.

四、含蓄条件句

有时为了表达的需要，在虚拟语气中并不总是出现If引导的条件句，而通过其他手段来代替条件句。

1.用介词短语代替条件状语从句。常用介词(短语)有:with, without, but for等。

e.g. 1）But for your help (If it hadn't been for your help), I couldn't have done it.

要是没有你的帮助，我就不可能完成这件事。

　　2). Without air, there would be no life on the earth.

　　3).What would you do with a million dollars? (=if you had a million dollars)

2. I was ill that day, otherwise, I would have taken part in the sports meeting. (副词)

3. He telephoned to inform me of your birthday, or I would have known nothing about it.（连词）

五、错综虚拟语气（也叫混合时间虚拟语气）

　　当条件状语从句表示的行为和主句表示的行为所发生的时间不一致时，动词的形式要根据它所表示的时间来调整。

1．主句和从句表示的时间不一致