工作英语对话:Making a Phone Call(2)

A: Can you show me how to use this phone?
B: Yes, I can help you with that. Pick up the receiver and hit one of the buttons. Do you hear a tone?
A: No, I don't hear anything.
B: Next you dial 9 on the keypad. You should hear the tone change. Did you hear it change?
A: I'm not sure.
B: OK. Well, after you get the line to change you have an outside line. Who are you trying to call?
A: I am trying to call a client.
B: To call a number on the outside you now just dial the number. For inside calls, punch in the extension number. Has someone given you an extension list?
A: No, I don't know anyone's extension.
B: All of the extensions are listed on the wall chart over there if you ever need help.