A rich man had only one son. The man loved his son very much. He sent his son to the best school in his city. But the son made some bad friends at school and he had many bad habits.

The man was worried about the habits of his son. He tried his best to correct his habits, but he could not succeed. One day he thought of a plan to teach his son a lesson. He went to the market and bought some fresh apples and a rotten (烂的) one. He came back to his home and called his son. He asked his son to put all the apples along with the rotten one in a box.

The son did the same. After some days the man asked his son to bring the apples. As the son opened the box, he was surprised to notice that all the apples have become rotten. He felt very sad.

The father told him to see how one rotten apple had spoiled (毁掉) all the rest. In the same way, one bad person could spoil all others. The father’s advice had the expected effect (效果). The boy left his bad friends and became good again.

It was only about ten at night, but it was cold. The cop stopped at doors as he walked along the street, trying each door to be sure that it was closed for the night.

Then the cop suddenly slowed his walk. Near the door of a darkened shop a man was standing. As the cop walked toward him, the man spoke quickly.

"It's all right, officer," he said. "I'm waiting for my best friend, Jimmy Wells. Twenty years ago tonight, I had dinner here with him. The next morning, I was to start for the West to find a good job. We agreed to meet here tonight."

The man near the door lit his cigarette. The light showed a pale, square face with bright eyes, and a little white mark near his right eye.

"It sounds interesting," said the cop. "I hope your friend comes all right. If he isn't here at ten, are you going to leave?"

"I am not!" said the other. "I'll wait half an hour, at least. Good night, officer."

"Good night," said the cop, and walked away.

There was now a cold rain falling and the wind was stronger, but the man waited.

About twenty minutes, a tall man in a long coat came hurrying across the street. He went directly to the waiting man.

"Is that you, Bob?" he asked, doubtfully.

"Is that you, Jimmy Wells?" cried the man at the door.

The new man took the other man's hands in his. "It's Bob! It surely is. I was certain I would find you here if you were still alive. We'll go to a place I know, and have a good long talk about old times."

At the corner stood a shop bright with electric lights. When they came near, each turned to look at the other's face.

The man from the West stopped suddenly and pulled his arm away. "You're not Jimmy Wells," he said.

"You've been under arrest* for ten minutes, Bob. But first here is something I was asked to give you. You may read it here. It's from a cop named Jimmy," said the tall.

The man from the West opened the little piece of paper. His hand began to shake a little as he read.

"Bob: I was at the appointed place on time. When you struck the match to light your cigarette I saw it was the face of the man wanted by Chicago Police. Somehow I couldn't do it myself, so I went around and got a plain clothes man to do the job. Jimmy."