A 10﹣year﹣old boy decided to study Judo（柔道）,although he had lost his left arm in a car accident.
He began his lessons with an old Japanese Judo teacher, Mr.Janaka. He was doing well，but he could not understand why the teacher had taught him only one move for quite a long time.
"Sir," the boy finally said，"I think I should learn more moves."
"But this is the only move you will ever need to know," the teacher answered. Not quite understanding, the boy kept training. Several months later, Mr. Tanaka took the boy to his first tournament（锦标赛）.The boy won his first three matches，using his one move to win. The boy was now in the final, and was surprised by his own success.
This time, his opponent （对手） was bigger, stronger, and more experienced. The referee（裁判） wanted to stop the match.
"No," the teacher insisted，"let him continue."Soon，his opponent lowered his guard. At that moment the boy used his move to beat him. The boy won the match and became the champion. On the way home，the boy and his teacher talked about every match. Then the boy asked what was really in his mind.
"Mr. Tanaka，how did I win the tournament with only one move?"
"You won for two reasons，" his teacher answered."First，you've almost mastered one of the most difficult throws in all of Judo. And second ，the only defense（防守） for that move is for your opponent(对手） to catch your left arm."
The boy's biggest weakness（弱点） had become his biggest strength.
