A sergeant was passing the barracks after lights out, when he heard some voices from inside. He threw open the door, and shouted: Listen, you guys! A few minutes ago you heard me say "Good night." What you must realize, is that when I say "Good Night," what I really mean is "Shut the f*ck Up!"
After a few seconds, from somewhere in the far back of the dark room: "Good Night, Sergeant."