—Goodbye.
A.—Hello. Are you Su Hai?
—No, I'm not.
B. —Hi, I'm Wang Bing.
—Hi, I'm Sam.
C. —Are you Yang Ling?
—Yes ,I am.
D. —Goodbye.
A. Goodbye!
B. Yes, I am.
C. No, I'm not. I'm Liu Tao.
D. Good afternoon!
—Hello, John.
A. Good afternoon, Moe.
B. Goodbye, Mike.
C. Yes, you're right.
D. Good morning, Miss Su.
—