1, Something urgent has come up.
2, Is that all?
3, I'm sorry to have taking so much of your time.
4, Sorry, I'd better go now.
5, Thank you for calling.
6, It's been nice talking to you.
7, Please say hello to everyone.
8, My other line is ringing.
9, Give me your number, I'll call you back.
10, Call me again anytime.