am的过去式是was， 为什么当表示虚拟语气，我希望我是一只鸟时，要用I wish i were a bird，而不用w

am的过去式是was， 为什么当表示虚拟语气，我希望我是一只鸟时，要用I wish i were a bird，而不用w am的过去式是was,为什么当表示虚拟语气,我希望我是一只鸟时,要用I wish i were a bird,而不用wa 为什么是I wish I were a bird 而不是I wish I was a bird 我希望像他一样.英文怎么讲?是 用虚拟语气 I wish I was like him?还是 I wish I were 改错：I wish I am rich.我知道wish后的从句要用虚拟语气,但I 后面到底用was 还是用were?这两 was不是is和am的过去式吗?were不是are的过去式吗?为什么可以用if i were a boy?而不用if i 省略if的虚拟语气if i were a bird可以省略成were i a bird吗 If I were a bird的英语语法问题?为什么用were 不用was? 当出现虚拟语气时,为什么am,is都用过去式were?可am和is的过去式并不是were啊! I WISH I WERE A BIRD.怎么这句子里面用WERE,不用WAS啊?是不是书上写错了 I wish I ____(be) a bird.答案是were, I wish I were here yesterday中为什么不用was