怎么用法?
问题描述：
怎么用法?
答
was 为 is 和 am 的过去式,与 is am 用法一致,只不过需在过去时使用was用于 I ,he ,she,it 以及 单个人作主语的句子.例如：I was born in 1998.He was a doctor three years ago.She was at home yesterday.It was M...