补全对话，将序号填在横线上。

A．Are they playing badminton, too? B．They are playing tennis. C．Yes, they are. D．They are running so fast. E．What are they doing?

Peter: Look at these boys. 

Kate: They are playing badminton.

Peter: How about these girls? 

Kate: No, they aren't.

Peter: Look! Are the teachers running?

Kate: 

Peter: