defencesn.防御工事名词defence的复数形式.=defenses.defencen.防御；答辩；防务defence in extremely frigid area高寒地区防御Defence Helicopter Flying School数据服务Defence Traffic Management Board国防交通管理局defence technique in falling down倒地防守技术defence against biological weapon生物武器防护Defence against Ballistic Missile反弹道导弹防御Defence Analytical Services Agency国防分析勤务署Defence Blood Transfusion Services国防输血服务defence forces development program防卫力量发展计划Defence Manufacturers' Association数据挖掘