虚拟语气的一个问题

Question

虚拟语气中有一个高级语法叫倒装
请问谁能告诉我什么是虚拟语气倒装???
还请问有什么用?(为什么要倒装?)

Answer 1

虚拟语气的倒装就是虚拟条件句中“if”的省略，这种省略一般是这样的：

比如：If he had turned off the lights last night, he would not have been blamed by his boss.

倒装为： Had he turned off the lights las night, he would not have been blamed by his boss.

变化过程实际上就是把带“if”的虚拟条件从句中的"If"省略，句式改为疑问句式。

Answer 2

就是在If从句中，凡是以should、were、had作为助动词的都可进行倒装
如：
If I were you,I wouldn't do it.变成Were I you, I wouldn't do it.
If you should have done it 变成 Should you have done it
If you had done it 变成 Had you done it
注意：如果had作为have的过去式不可倒装
如：If you had a plate 不能倒装

Answer 3

在if引导的虚拟条件句中，若有were, had, should, 在书面语中可省去if ,将were等提到主语前，形成倒装。
Should there be a good film tomorrow. I would go to the
theatre with you.
Were it not for your help. I wouldn' t be succeed.