有关电话号码的英文缩写

问题描述:

有关电话号码的英文缩写
印度客户的一个电话号码是这样的:
Desk:+91-44-1234556 xtn:4556

Mean :" Extension " .It's a key phone system for the office.Once u get through the line on the desk,need to transfer the line to the extension number.