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    One day, Mr and Mrs White go shopping by car. They stop their car near a shop. They buy many things from the shop. And the things are very heavy, so they want to put them into their car. But Mr White can't open the door of the car. "Let's ask a policeman for help." says Mrs White. They ask a policeman to help them. The policeman is very friendly to help them open the door of the car. At that time a man comes up and shouts (叫), "What are you doing with my car?" Mr and Mrs White look at the number of the car, and then they say sorry to the man.