was的用法是什么?

was 是am is 过去式were 是are 过去式

was是英文单词am（vi.是； v.aux.; abbr.）的第三人称单数过去式，同时也是多个英文词组的简称。
因为 be 动词am对应的过去式是was
当你要表述过去发生的事情的时候，要把时态改一下，
而且改了之后注意其他动词的时态，也应该是过去时

was 是am is 过去式 ；were 是are 过去式 .
具体用法如下：
1.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 Monday yesterday.
Mike wasn't at home this morning.
2.were用于you,they,we 以及两个以上的人作主语的句子.
例如：
You were at home yesterday.
They were at the playground an hour ago.
We were singing in the room an hour ago.