为什么am not不能简写成amn't

为什么am not不能简写成amn't I am为什么不能简写 am not 的缩写是amn't吗 i am your father ,___ A.amn't B,am not C,isn't D,aren't am not为什么不能缩写 I‘m a student,_____?(aren't I 和 amn't I 和 am not I和isn't I应该 they are 可以简写成they're,那么these are为什么不能简写成these're I am right.怎么反问?是amn't I,aren't I,还是ain't I should not 能否简写为shouldn't. I'm right ,____ I.A am B.aren't C.amn't 为什么不能I am no happy 只可以I am not happy? I will not change my mind 为什么不能改成I am not going to change my