什麼情况下用am are is was were 什麼时候不用..
什么情况下be是不用变成am is are was were 的
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
用“am/is/are/was/were"填空
用am is was are were造句
用am,is,are,was,were填空.
is----------was.are---------were.am---------?
am is are was were
be.am.is.are.were.was.been.being.分别是什么时候用的
用is,was are,were am,was造句,
英语用am,is,are,was,were造句?
1、用 am ,is ,are ,was ,were ,填空
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