我们的部队在前方3条战线上作战。 Our armies were fighting on three fronts.
在各条战线上都有精力充沛朝气蓬勃的青年人。 On every front there are young people abounding in vigor and vitality.
游击队在那个省开辟了一条新战线。 The guerrillas opened up a new front in that province.
我已决定派一名特工人员去收集情报，但是如果他被抓住的话，那就会给外交战线带来麻烦。 I've decided to send in an agent to gather intelligence, but if he gets caught it will stir up a hornet's nest on the diplomatic front.