常见缩写:I'm= I am 我是。she's= she is 她是。he's= he is 他是。it's=it is 它是。they're=they are 他们是。you're=you are 你是。what's=what is 什么是。
*am / is / are表达的意思是“是”，用在人或物的后面。变问句，be提前，句尾问号要配全。应用时多注意缩写形式要牢记:I'm=I am。you're=you are。he's=he is she's=she is it's=it is。we're=we are you're=you are they're=they are ...
be动词用法顺口溜 (1)我用am，你用are，单三is，复数are。 (2)I用am，you用are，非I非you是is，复数全部都用are。 (3)代词主格的顺口溜： I是我来we复数，你和你们都用you； he，she，it男、女、它，复数一律把they用。
