根据对话的情景，从方框中选择适当的句子填在画线处，使对话完整通顺。其中有两项是多余的。

A: Hello! May I speak to David, please?

B: This is David speaking. Who's that?

A:   

B: Hello, Li Lei.    

A: I'm doing my homework.

B: I think you are learning physics.

A: Yes. You're right.  

B: Because physics is your favorite subject.

A: David, we want to play soccer this afternoon.   

B: Yes, I'd love to.   

A: We want to meet on the playground at 1:00 p. m. See you then. Bye.

B: Bye-bye.

A. When and where will we meet? B. I'm Li Lei. C. How are you? D. What are you doing? E. Would you like to come with us? F. This is Li Lei. G. Why do you think so?