Complete the following dialogues with proper sentences(选出适当的句子，完成下列对话，用A、B、C等表示)

　　　A．When will he be back in the office?

　　　B．Can I speak to Mr. Hamilton, please?

　　　C．And what's your telephone number?

　　　D．Can I take a message?

　　　E．No, that's not a good idea.

　　　F．Could you tell me your name again?

　　　G．Yes, that's right.

A：Hello.

B：　　1　　

A：I'm sorry. He's not here. 　　2　　

B：Yes. This is Mary Robertson from CITS. I'm returning his call. 　　3　　

A：I'm not sure. If you leave your number, he'll call you when he comes back.

B：　　4　　 I have meetings all afternoon. I'll call him again.

A：All right. I'll tell him. 　　5　　

B：Yes, it's Mary Robertson.

A：And you're from CITS?

B：　　6　　

A：Okay, Ms Robertson. I'll give him the message.

B：Thank you.

A：You're welcome. Goodbye.

1．(　　)　2．(　　)　3．(　　)　4．(　　)　5．(　　)　6．(　　)