考点梳理

If 省略句 在虚拟条件状语从句中可省略if, 把were, had, should提到句首，变为倒装句式。

1. If I were at school again, I would study harder. Were I at school again, I would study harder. 2. If you had come earlier, you would have caught the bus. Had you come earlier, you would have caught the bus. 3. If it should rain tomorrow, we would not go climbing. Should it rain tomorrow, we would not go climbing.