Last Sunday, Bob had a （特别的）experience because he met an （事故）. On that day, all his classmates went hiking （除了）him, because he missed his grandmother very much. She was very old and lived （单独地）far away from the town. On the way there, （当……的时候）he was walking, a car came fast and hit an old man down. However, the driver didn't stop to help the poor old man. （代）, he went away. Bob felt so angry and afraid. He found （没人）there and he had to call the police. The police came right away and the old man was taken to hospital quickly. （幸运地）, the old man was still alive. As a result, Bob got to his grandmother's home a bit late. After his grandmother （听到）this, she smiled and said he （是）really a good boy.
