One day a farmer went out for a walk with his little son. The farmer put on a pair of wrong shoes, one with a thick sole (鞋底) and the other with a thin one. So as he began to walk, he felt very uncomfortable (不舒服). When he was just out of the house, he turned to his son and said, "Why should one of my legs be longer than the other today"
The son looked at his father’s legs carefully as he was walking and then laughed," Oh, no, Daddy, your legs are all right. You have put on the wrong shoes."
The farmer was very happy to hear that and said to himself, "What a clever son I have got!" Then he asked his son to go back and get the other pair of shoes for him. The farmer had only two pairs of shoes.
When the son ran back to the house, he found that the other pair was also a pair of wrong shoes.
He had to return to his father with nothing in his hands and said out of breath (气喘吁吁地), "It’s no use changing them, Daddy! The shoes at home were not a pair, either!\
One shoe has a thicker sole than that of the other.