(iii) Operation and maintenance of about 17,000 telephone, trunk ports and facsimile lines connected to the private branch exchange (PBX) at Headquarters and implementation of approximately 14,000 user requests for moves and changes;
㈢ 操作和维护总部的专用交换机联接的约17 000门电话、中继端口和传真线路，并处理约14 000个用户的移动和变更电话的要求；