am.is,a的过去式?检点
问题描述：
am.is,a的过去式?
检点
答
was
答
is,am都是was,
are是were.
答
am过去式：was.
is过去式:was.
are过去式：were.
答
is am 都是was, are 是were
答
a没有过去式
am is 的过去式是was
are是were.