同义词
1)local telephone system,urban telephone system,city telephone,市内电话2)local telephone exchange,市内电话局3)city telephone switching system,市内电话交换系统4)numbering of local network,市内电话网(本地网)编号5)local network,urban telephone network,市内电话网;本地（通信）网6)Integrated Telecom Business Management by Computer,市内电话业务计算机综合管理
