Be动词的用法口诀 我(I)用am，你(you)用are， is连着他(he)、她(she)、它(it)。单数名词用is，复数名词全用are。变疑问，往前提，句末问号莫丢弃。变否定，更容易，be后not莫忘记。疑问否定任你变，句首大写莫迟疑。1我(I)用am,你(you)用are,is连着他(he),她(she),它(it)；这些是固定用法：I am a boy.(你不能说 I is a boy)You are a student.He is a boy.She is a girl.It is a cat.2单数名词用is,复数名词全用are.(主语个数是一个时,谓语用单数is,主语个数为2个或以上,谓语用复数are.)The book is over there.(一本书）The books are over there.（多本书）.They/We/You are students.3变疑问,往前提,句末问号莫丢弃.(陈述句中谓语为is,are,am时,变疑问句只将其提
