be动词的用法一、be动词的种类be动词包括“am”, “is”, “are”三种形式。（1）第一人称单数(I)配合am来用。句型解析析：I am+I am twelve .I am slim. I am a student. I am a boy.（2）第二人称(You)配合are使用。句型解析：You are+You are my good friend. You are a good student .You are pretty.（3）第三人称单数(He or She or It)配合is使用。句型解析：She(He, It) is +She is a good girl.She is short .She is a teacher.（4）人称复数 (we /you/they)配合are使用。句型解析：We (You, They) are +We are in Class 1,Grade 7.They are my friends.You ar
