The whole town is patrolled by police because of the possibility of riots. 为防止发生骚乱整个城镇都有警察巡逻。
A security guard with a dog patrols the building site at night. 夜间一名保安带着一条狗在建筑工地巡逻。
Coastguards found a deserted boat while patrolling (along) the coast. 海岸警卫队在岸边巡逻时发现了一条被遗弃的船。