defence(Britain); defense(US)

• 化学防御

  chemical defence

• 积极防御

  active defence

• 加强防御

  strengthen defence

• 转为防御

  become defensive

• 防御地带

  zone of defence

• 防御工事

  fortification

• 防御战术

  defensive tactics

• 防御力量

  defensive strength

• 不能消极防御，要主动进攻。

  One should take the initiative and attack instead of passively defending.