虚拟语气中为什么用were

问题描述:

虚拟语气中为什么用were
Mary loves the baby so much as if she were his mother.
这其中were为什么不改成was?

这是虚拟语气的固定用法.虚拟语气对现在的虚拟有两种,【实意动词用过去式,be动词用were(不能用was)】.这两种分别举例如下:
If he finished his homework, I would be so surprised. 如果他现在完成了作业,我会很吃惊的.
If I were you , i would go to the cinema. 如果我是你,我就去电影院.那决不能用was了吧是的,不能用was,不管主语是什么,只要是be动词,都要用were。