I wish he were here.为什么是were不是was阿

I wish he were here.为什么是were不是was阿 歌词sometimes i wish i were an angle为什么这里用的是were不是was. I wish I were here yesterday中为什么不用was if he were here i would beat him 为什么不是 if he was here 不是过去式吗 下面这句话,为什么是I wish I was 而不是 I wish I were? 为什么是I wish I were a bird 而不是I wish I was a bird I wish you were here you （was,were） I (was,were) he (was,were) 英语翻译这里为什么是were不是was 为什么I wish I were you用were呢? I wish I were “If I were a boy”的谓语为什么是“were”?“am”的过去时不是“was”吗?