题目内容
Section B
Directions: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A, B, C and D. You should decide on the best choice.
If the salinity(含盐量)of ocean waters is analyzed, it is found to vary only slightly from place to place. Nevertheless, some of these small changes are important. There are three basic processes that cause a change in oceanic salinity. One of these is the subtraction of water from the ocean by means of evaporation—conversion of liquid water to water vapor. In this manner, the salinity is increased, since the salts stay behind. If this is carded to the extreme, of course, white crystals of salt would be left behind.
The opposite of evaporation is precipitation(降水), such as rain, by which water is added to the ocean. Here the ocean is being diluted(稀释)so that the salinity is decreased. This may occur in areas of high rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increased by the subtraction of water by evaporation, or decreased by the addition of fresh water by precipitation or runoff(形成地表水部分的降雨).
Normally, in tropical regions where the sun is very strong, the ocean salinity is somewhat higher than it is in other parts of the world where there is not as much evaporation. Similarly, in coastal regions where rivers dilute the sea, salinity is somewhat lower than in other oceanic areas.
A third process by which salinity may be altered is associated with the formation and melting of sea ice. When seawater is frozen, the dissolved materials are left behind. In this manner, seawater directly beneath freshly-formed sea ice has a higher salinity than it did before the ice appeared. Of course, when this ice melts, it will tend to decrease the salinity of the surrounding water.
In the Weddell Sea, off Antarctica, the densest water in the oceans is formed as a result of this freezing process, which increases the salinity of cold water. This heavy water sinks and is found in the deeper portions of the-oceans of the world.
The best title of the passage can be"______"
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听力原文：M: Hey, Mary, let's have a cup of coffee and a piece of pie.
W: Oh, I'd like to, but I've got to be getting along.
What did you learn about Mary？
In many Western societies, such as the United States or Canada,【C1】______many different nationalities, religious groups and cultural orientations, individualism and independent thinking are【C2】______valued. And these values are reflected by the education systems in these countries. Teachers【C3】______the qualities that make each student special. Students are【C4】______expected to memorize information; instead, they are encouraged to【C5】______, find answers on their own and【C6】______individual solutions. At an early age, students learn to form. their own ideas and opinions, and to ex press their ideas in class discussion.
In Japan,【C7】______, the vast majority of people share the same language, history, and culture. Perhaps for this reason, the education system there reflects a belief in group goals and traditions【C8】______individualism. Japanese schoolchildren often work together and help one another on assignments. In the classroom, the teacher is the main【C9】______of knowledge: He or she lectures, and the students listen. There is not much discussion;【C10】______, the students recite rules or information that they have memorized.
The advantage of the education system in Japan is that students there learn the social skill of cooperation.【C11】______advantage is that they learn much more math and science than most American students. They also study more hours each day and more days each year than their North American【C12】______do. The system is demanding, but it【C13】______children for a society that values discipline and self-control. There are, however, disadvantages. For one thing, many students say that after an exam, they forget much of the information they memorized.【C14】______, the extremely demanding system puts enormous psychological pressure【C15】______students, and is considered a【C16】______factor in the high suicide rate among Japanese school-age children.
The advantage of the education system in North America,【C17】______, is that students learn to think for themselves. They learn to【C18】______to make decisions and take action without someone telling them what to do. There are drawbacks, however.【C19】______other things, American high school graduates haven't studied as many basic rules and facts as students in other countries have. And many social critics【C20】______the high crime rate in the US at least partially to a lack of discipline in the schools.
【C1】
A．An engine room.B．A big kitchen.C．A great theatre.D．A high building.
听力原文： For many years, T-shirts were simple short-sleeved undershirts for men and boys. T-shirts used to be of one color—white. And since they were worn under shirts, they were generally not seen.
Today the T-shirt has become fashionable. It can be seen everywhere and on everyone. Women and little children wear T-shirts as teenagers, university students, and men from all walks of life. T-shirts are worn on playground, at the beach or in town. They can also be worn for work. Yet T-shirts remain relatively inexpensive and long wearing, as well as easy to care for. [29] Smart but comfortable and convenient to wear, they have be come one of America's newest ideas of fashion.
Although T-shirts are now available in a wide variety of bright materials and styles, [30] the most popular kind is the traditional cotton T-shirts with a slogan or picture printed on the front. As T-shirts are becoming more and more popular, [31] new designs are coming up all the time.
(30)
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