1.Hang on please. 请稍等，请不要挂断
A:June, hang on please. I will be right back.
2. Hang up 挂断
A: She hung up on me.
B: Did she? she must've been mad.
3.I'll call him back. 我会再给他打电话。
A: I'll call him back.
B: Okay, he will be back at three.
A: Could you put Alice on?
B: She is all tied up.
5.Telephone conference 电话会议
A: Do you have telephone conference tonight?
B: I do. I have telephone conference almost every night.