题目内容：

根据所给提示，写出单词的正确形式。每空限填一词。

Last Sunday, Bob had a special experience because he met an1.（事故）. On that day, all his classmates2.（自愿做）to clean up the city parks except him, because he missed his grandmother very much. She was very old and lived3.（独自，单独）far away from the town. On the way there, when he was walking, a car came fast and4.（撞，击）an old man. However, the driver didn’t stop to help the poor old man.5.（代替，反而）, he went away. The old man was6.（躺）on the road and couldn’t move. Bob was 7.（彻底地，完全地）shocked. As there was nobody else on the road, he8.（领会，认识到）he had to call the police quickly. The police took the man to hopital and the old man was saved by the doctor. As a result, Bob got to his grandmother’s home a bit late. After hearing the9.（事实，实情）, his grandmother smiled and said, “You are a clever and kind boy. You saved the man because of your right10.（决定）.”