1、He is ( )our teacher.He is also our friend.

问题描述:

1、He is ( )our teacher.He is also our friend.
2、It was late while he came to my house last night.
(从划线部分找出错误,并改正.划线部分为A.was late B.while C.to my house )
请说明原因

1 not only
2 B while-->when