一天我正在屋里看一本有趣的书，这时爸爸进来要我给他买一瓶啤酒。我下楼骑上自行车就去了。我到了商店门口的时候，没锁自行车就进去了。几分钟后，我从商店里出来，突然看见一个人骑在我的自行车上，要逃跑。我赶紧跑着追他。可他骑得太快，我追不上他。就在那时，一辆警车正好经过。我跑去请求他们帮助。自行车永远也没有汽车跑得快，很快小偷就被抓住了，我的自行车也失而复得。

     one day, while i was reading an interesting book, my father came in and asked me to buy a bottle of beer for him. i went downstairs and rode on my bike. when i reached the shop, i entered without locking my bike. a few minutes later, i came out of the shop. suddenly i saw a man riding on my bike and trying to get away with it. i quickly ran to him. but he was too fast. i couldn't catch up with him. just then, a police car happened to come along. i went over and asked them for help. they hurriedly drove after the thief. a bike can never run faster than a car. so the thief is caught in no time. i got my bike back again.