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    Michael and Derek are good friends, but they like to pull each other's leg sometimes. One day during the holidays they decided to go to London together. They went to the station and bought their tickets. When the train came in, Michael broaden in first and without knowing it, dropped his ticket in the platform as he got into the carriage（车厢）. Derek, who was close behind saw the ticket fall and quickly picked it up. Without a word to his friend, he put it in his pocket.
    After they had been in the train a little while, they heard the ticket inspector coming down the corridor, shouting, "tickets, please!" Michael looked for his and of course couldn't find it.
    "Oh, dear, I can't find my ticket, Derek," he said.
    "Have another look, Michael, it must be somewhere," said Derek.
    "No, I can't find it anywhere. What shall I do?"
    "Perhaps you had better hide under the seat, then the inspector won't know you are here." So Michael crawled under the seat as fast as he could and lay perfectly still. Presently the door opened and in came the inspector, "Tickers please!" he said.
    Derek handed him two tickets and said, "This is mine. The other belongs to my friend, who prefers to travel under the seat."