Bill and Fred were students and they were friends. They didn’t have much money, so when it was time for their summer holidays, Bill said, “Let’s take our holidays in a trailer （旅行车）．It’s cheaper than a hotel. I can borrow my father’s trailer. ” Fred was very happy, so they got into the trailer and began their holidays. They wanted to get up early the next day to go fishing, but they didn’t have an alarm clock. “That’s all right, Bill, ” said Fred. “I’ll put these small pieces of bread on the roof of the trailer tonight and they’ll wa