Mike wants to go to the post office, but he doesn't know the way. He sees an old man in the street. He says, "Can you tell me the way to the post office?" The old man doesn't answer.
Mike gets angry and shouts, "Old man, tell me the way to the post office! Can you hear me?" The old man looks at him and says, "Walk along this road and then turn left at the second crossing. Turn right, and turn right again. Then you will find the post office."
Mike does what the old man says. He walks for half an hour. He meets the old man again. He is very angry and shouts, "Why do you tell me the wrong way?" The old man says, "Because you are not polite. You ask in the wrong way."