verb · to extinguish or put out (fire, light, etc.), or to go out

离开教室之前，请记得把所有的灯都灭掉。

verb · to drown or be submerged in water

大水灭顶，情况万分紧急。

verb · to exterminate, wipe out, or destroy completely

这些害虫必须彻底消灭。