dutyfreeadj.免税的adv.免税地dutyn.义务；职责；责任；税；关税duty ratio loss占空比丢失duty free goods免税货物,免税品Duty Motor Boat值勤机动船duty on alcohol酒精税duty management责任管理duty free entry免税进口duty allocation责任划分duty paid proof[经] 完税凭证duty of officer军官之职duty assignment任务分配