Listen to the tape then answer the question below. 听录音，然后回答以下问题。 What are the St. Bernard dogs used for?
The Great St. Bernard Pass connects Switzerland to Italy. At 2,473 metres, it is the highest mountain pass in Europe. The famous monastery of St. Bernard, witch was founded in eleventh century, lies about a mile away. For hundreds of years, St. Bernard dogs have saved the lives of travellers crossing the dangerous Pass. These friendly dogs, which were first brought from Asia, were used as watchdogs even in Roman times. Now that a tunnel ahs been built through the mountains, the Pass is less dangerous, but each year, the dogs are still sent out into the snow whenever a traveller is in difficulty. Despite the new tunnel, there are still a few people who rashly attempt to cross the Pass on foot. During the summer months, the monastery is very busy, for it is visited by thousands of people who cross the Pass in cars. As there are so many people about, the dogs have to be kept in a special enclosure. In winter, however, life at the monastery is quite different. The temperature drops to -- 30 o and very few people attempt to cross the Pass. The monks prefer winter to summer of they have more privacy. The dogs have greater freedom, too, for they are allowed to wander outside their enclosure. The only regular visitors to the monastery in winter are parties of skiers who go there at Christmas and Easter. These young people, who love the peace of mountains, always receive a warm welcome at St. Bernard's monastery.
