( ) My mother works _____ a bank . A. in B. on C. at
( )Mike: Good afternoon, Mrs. White! Mrs. White:
( )Sarah: Good morning, Mr. Black! Mr. Black:
( )Mrs White: Hello, Mike. Mike:
( )Sarah: Bye, Wu Yifan. Wu Yifan:
( )你向你的妈妈介绍你的同学Sarah时,你说: A . Hello, Sarah. B. Hello, I’m Sarah. C . This is Sarah.