2.在非if引导的状语从句中

虚拟语气用在when，unless，lest，for fear that，suppose(that)，supposing(that)，provided(that)，providing(that)，on condition that，even if/though及in case等非if引导的状语从句中。

The government prepared to award them when the experiment should be completed．

政府已准备在实验完成后嘉奖他们。(含有难得完成的意思)

He was punished lest he should make the same mistake again．

他被处以惩罚以免再犯。

Unless I were well，I wouldn't be at work．

除非我好了，否则我不会去上班。

He handled the instrument with care for fear that it should be damaged．

他小心地弄那仪器，生怕把它弄坏。

He can use the car on condition that he should return/returns it tomorrow．

如果明天车能还回来，他就可以把车借去。

提示：

on condition that从句的虚拟语气不是强制性的。

Suppose you were given a chance to get the job，would you accept?

假如你有机会得到那份工作，你会接受吗?

Supposing(that)you were left alone on a desert island，what would you do?

假若你只身被留在一个荒岛上，你会怎么办?

Even if he were here，he wouldn't be able to help you．(与现在情况相反)

即使他在这儿，他也不能帮你。

Nothing could have saved him even if he had been tended without delay．(与过去情况相反)

即使他当时得到了及时的照顾，他的生命也无法挽救。

提示：

与if一样，上述词语引导的状语从句亦可用陈述语气，表示可能实现或发生的事。