Doctor : Let me tell you a story: « There was once a Hunter who always carried a gun wherever he went. One day he took out his Umbrella instead of his Gun and went out. A Lion suddenly jumped infront of him. In order to scare the Lion, the Hunter used the Umbrella like a Gun, and shot the Lion, then it died!
Guy : Nonsense! Someone else must have shot the Lion..
Doctor : Good! You understood the story. Next patient please..