A boy who was cleaning shoes in the street said to a young man passing by (路过的), "Let me clean your shoes." The young man said, "No, thank you." "You may pay me only a pound, sir." said the boy. But the young man refused again. Then the boy said, "____" The young man agreed to this, and soon one of his shoes was bright. The man put the other shoe on the boy, but the boy didn't clean it unless (除非) the man give him two pounds (英镑) for his work. The young man didn't agree to pay anything and went away.
But the dirty one looked so bad that he couldn't walk away. He had to turn back and gave the boy two pounds. In a very short time his shoes were bright.