run down耗尽能量：The battery has run down
run into遇见,遇到We ran into thick fog on the way home.
run off复制复印Could you run off 20 copies of the agenda?举行进行（赛跑）The heats of the 200 metres will be run off tomorrow.
run out用完耗尽Time is run out for the trapped miners(被困矿工的时间不多了）