2014年英语四级考试听力理解4

　　Passage 1

　　Your professor has asked me to talk to you today about the topic that should be of real concern to civil engineers: the erosion of US beaches. Let me start with some statistics. Did you know that 90% of the coast in this country is eroding, on the gulf of Mexico for instance, erosion averages 4 to 5 feet per year. Over the past 20 years, there has been an increase in building along the coast, even though geologists and environmentalists have been warning communities about problems like erosion. Someway communities have tried to protect their building and roads and to build seawalls. However geologists have found that such stabilizing structures actually speed up the destruction of the beaches. These beaches with seawalls, called stabilized beaches, are much narrower than beaches without them. You may wonder how seawalls speed up beach loss. The explanation is simple. If the flow of the beaches is gentle, the water energy is lessened as it washes up along the shore. It is reduced even more when it returns to the sea as it doesn’t carry back much sand. On the other hand, when the water hits the nearly vertical face of the seawall, it goes straight back to the sea with the full force of its energy and it carries back a great deal of sand. Because of the real risk of losing beaches, many geologists support a ban on all types of stabilizing construction on shore lines.

　　Questions 1 to 4 are based on the lecture you’ve just heard.

　　1. What is the speaker mainly discussing?

　　2. Why do communities build seawalls?

　　3. How does a gently sloping beach help prevent erosion?

　　4. What would the speaker probably advise engineers to do?

　　Passage 2

　　In Britain the biggest number of working foreigners comes from the odd system know as ‘au pair’. Every week hundreds of girls arrive from strange capitals to live with English families. They are called au pairs. An au pair girl stays with the family and has free food and lodging. In return she does light work in the house. This system began as a genuine exchange, but now has become a commercial bargain between families who need help and girls who need to learn English. As learning languages has become more important, so the numbers involved have gone up.

　　The system succeeds fairly well so far as teaching the girls English is concerned. But it is debatable how far it increases international friendship. There is a basic conflict of objectives—the hosts want cheap labor, the girls want leisure and language. The girls often find it hard to meet English people of their own school ages, for the language schools and clubs are made up of other foreigners.

　　In spite of its shortcomings, the au pair system has probably played some role in breaking down frontiers. The British Vigilance Society estimates that 15 percent of the girls are very happy, 15 percent very happy, and 70 percent more or less content; but only a small minority keep in touch after they go back home.

　　Questions 5 to 7 are based on the passage you’ve just heard.

　　5. What does the au pair system mean now?

　　6. What is NOT mentioned as an advantage of the au pair system for the girls?

　　7. How do the girls feel about the system?