关于be动词 am,is,are 的过去式 was 和were 的用法.我已经知道was 和were 是前者的过去式.

关于be动词 am,is,are 的过去式 was 和were 的用法.我已经知道was 和were 是前者的过去式. be+过去式 和 was/were+过去式的区别 一般过去式用来表示am is are的was和were有什么区别? 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 填写适当的动词be(am, is, are, was, were) be动词用法be动词什么情况用现在式am,are,is .什么情况下用过去式was,were ,什么情况下用过去分词be was、were的用法和与is、am、are的区别 助动词和实义动词能做谓语 am is are was were +doing这里的am is are was were were 和 was 的用法. was 和were的用法? was和were的用法 在英语一般过去式中was和were的后面应加动词什么形式啊?