根据短文内容，在各题所给的三个选项中，选出一个最佳选项。（短文听两遍） 1. Where does David work? A. In a hospital. B. In a library. C. In a supermarket. 2. How long does he have for the summer holidays every year? A. Five days. B. Seven days. C. Thirty days. 3. Why did he take the train to San Francisco? A. Because he wanted to save money. B. Because he wanted to see the United States. C. Because it's more comfortable than taking a plane. 4. Where did he get off the train? A. In a small town. B. In New York City. C. In San Francisco. 5. How did he return to New York? A. By plane. B. By bus. C. By train.