根据短文内容判断正误

One day Mr and Mrs White went shopping by car. They stopped their car near a shop. They bought a lot of things and wanted to put the things into the car. But Mr White couldn't open the door of the car, so they asked a policeman to help them. The policeman was very friendly. He started to open the car for them. Just then a man came up and shouted. "What are you doing with my car?" Mr and Mrs White had a look at the cars number and they were frozen there. It wasn't their car.