短語詞組短語private branch exchange switchboard 內(nèi)部通信小交換機;專用小交換機branch h type switchboard 分立型配電盤private branch switchboard detail 專用交換臺private branch switchboard 專用交換臺;用戶交換臺;用戶總機The Branch Switchboard 主干交換機 返回 branch switchboard