阅读短文，回答下面的问题。

    Mr Brown lived in a small town, but he worked in a big city. So he moved there with his wife and two children last Tuesday.

    The next day, Mr Brown was washing his new car. When a friend came, the friend stopped and looked at the new car for a minute. Then Mr Brown turned and saw him.

    The friend said, "That's a new car. Is it yours?"

    "Sometimes," Mr Brown answered.

    The friend was surprised. "Sometimes?" he asked, "What do you mean?"

    Mr Brown answered slowly, "Well, when there is a party in town, my daughter Jane drives it. When there is a football game, it's my son Joe's turn. When I wash it and it looks really nice and clean, my wife Linda uses it. And when it needs cleaning, it's mine."