听力原文：A: How is Canada's climate? Is it intolerably cold in winter? B: People tend to think that as Canada is a northern country, its winters must be harsh and long. But contrary to the popular belief, on the whole, Canada is a very sunny land with a distinctive change of seasons. Of course, since Canada is such a vast country, its climate varies greatly from region to region. A: Really? That sounds amazing to me. B: Yes, when talking about Canada's climate, people usually divide it into six climatic regions. A: In general, how are the four seasons divided? B: Generally speaking, spring begins in mid March and ends in mid May. It is regarded as a transitional time in Canada. Summer lasts for about four months. Autumn is the shortest season, less than about three months. Winter is the longest season in most of Canada. A: Is summer in Canada very hot? B: No. The summer in Canada is warm and sunny. For most people, it is the best season for fun and relaxation. A: How about autumn? B: Autumn is very beautiful, though it is brief. A: Is winter in Canada terribly cold? B: Well, the winter in Canada is indeed very long, but it is not gloomy because there is much sunshine. So many people enjoy skiing and skating in winter. (20)