I

⑴Hi, Sam.    

⑵Hello! Are you Liu Tao?    

⑶Goodbye, Miss Li.    

⑷Good afternoon, Su Hai.    

⑸Hi, I'm David.    

II

A. Hi, I'm Liu Tao.

B. Good afternoon, Wang Bing.

C.Goodbye, Mike.

D.Yes, I am. 

E.Hi, Bobby.