选择合适的句子补全对话。

A．Let's go.

B．What will you do after school today?

C．You should do your homework after school.

D．When the light is green, we can go.

E．You can't play in the road.

Mother: ______ It's dangerous.
Sam: Sorry, Mum.
Mother: Sam! You should be careful!
Sam: Yes! Mum, the light is red. ______
Mother: Oh, no, Sam! When the light is red, you can't go.
Sam: Oh, sorry, Mum! And when should we go?
Mother: ______ 
Sam: I know that now, Mum!
Mother: ______
Sam: I will play chess with my friends.
Mother: No! ______