If the salinity 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 carried to the extreme, of course, white crystals of salt would be left behind.The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted 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.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.1.According to the passage, the ocean generally has more salt in（ ） .2.The world “it” in line 4(paragraph 4) refers to（ ） .3.Why does the author mention the Weddell Sea?4.Which of the following is NOT a result of the formation of ocean ice?5.What can be inferred about the water near the bottom of oceans?
A.coastal areas B.tropical areas C.rainy areas D.turbulent areas
问题2：
A.sea ice B.salinity C.seawater D.manner
问题3：
A.To show that this body of water has salinity variations B.To compare Antarctic waters with Arctic waters C.To give an example of increased salinity due to freezing. D.To point out the location of deep waters
问题4：
A.The salt remains in the water. B.The surrounding water sinks. C.Water salinity decreases. D.The water becomes denser.
问题5：
A.It is relatively warm. B.Its salinity is relatively high. C.It does not move. D.It evaporates quickly.
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Read the following short paragraph carefully and then translate it into English.
虽然人人都需要一个职业是事实——最好是工资高的。但同样确实无误的是 我们的文明已经在与我们自己的专业相去甚远的领域积累了多得令人难以置信的知识， 而我们也具备了了解这些其他方面知识的更好条件——无论他们是科学的贡献还是艺术上的成就。同样确实无误的是，在研究不同智慧时，我们可以学会如何思考。更重要 的也许是教育教会我们看到事物之间的联系，并看到我们的当前需求以外的东西。从长 远的观点来看，这正是教育所真正应该做到的，而我认为它也能够做到的。