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    A smuggler(走私犯) drove to the border. When a soldier looked in the truck， he was surprised to find six big bags.

    “What's in them?” the soldier asked.

    “Dirt，” the smuggler answered.

    “Take them out，” the soldier said. “I want to check them.”

    The smuggler opened the bags， and sure enough， each one of them was filled with dirt. So the soldier let him go.

    A week later， the smuggler came back， and once again， the soldier looked in the truck.

    “What's in the bags this time?” he asked.

    “Dirt， more dirt，” said the smuggler.

    Not believing him， the soldier checked the bags and， once again， he found nothing but dirt.

    The same thing happened every week for six months， and the soldier finally became so frustrated(沮丧的) that he left and worked as a waiter in a restaurant. Then one night， the smuggler went to the restaurant and had a drink. The waiter saw him and said， “Listen! Drinks are free tonight if you tell me what you were smuggling all that time.”

    Slowly， the smuggler got close to the waiter and said， “Trucks.”