二、对话理解 听下面三段对话，从每小题A、B、C三个选项中，找出相应问题的最佳答案。（每小题1.5分，共15分）
听第一段对话，回答6-8小题。
6. What is Susanna interested in?
A. China’s history. B. The geography of China. C. China’s lit erature.
7. Which dynasty was Zheng He from?
A. The Yuan Dynasty. B. The Ming Dynasty. C. The Qing Dynasty.
8. How long did his ocean journeys last?
A. 26 years. B. Nearly 28 years. C. Half a century.
