A piece of chalk... When I was studying at the University, we have a lesson in a great lecture hall, because it was joined with the other classroom. So, there were two doors for one place. The second door didn’t seal yet. The teacher was an old man, about 76 years old. He was a little blind and a little deaf. It so fell out that there wasn’t any piece of chalk. The old man asked to take the piece of chalk from the other classroom and bring it back. One girl was decided to complete this mission by herself. She left the audience and knocked on the second door in ten seconds. She opened the door and asked: Do you have a piece of chalk. Our teacher answered, without even looking at her: No, we don’t. I’ve already sent a pupil to take it from the other classroom. The girl came back to the first door and said: They don’t have the piece of chalk. The old man replied: I know, someone was coming from the other classroom and asked it as well.