几只武装民船经常在这个海峡的进口附近巡航。

Several privateer often cruise near the entrance of the channel.

卢西塔尼亚号不是一条民船，而是武装商船。

And itwasnt a civilian ship, it was carrying arms for sale.

武装民船： 为交战国征用以攻击敌方船只（常是商船）的私有武装船只。

Privateer: Privately owned vessel a state at war to attack enemy ships, usually merchant vessels.