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请在第___________处填上正确答案．阅读材料，回答下面的题目： What We Take from and Give to the Sea As long as we have been on earth, we have used the sea around us. We take from the ocean, and we give to it. We take fishes from the ocean-millions of kilograms of fish, every year, to51millions of people. We even52their bones for fertilizer. We take minerals from the ocean. One way to get salt is to53seawater in shallow basin and leave until it evaporates( 蒸发 ). Along with salt, other minerals are left 54 evaporation.Much gold and silver drift dissolved in the waters of the sea, too. But the sea does not give them 55 by simpleevaporation.56gifts from the sea are pearls, sponges( 海绵) and seaweed. Pearls57jewelry. Natural sponges become cleaning aids. Seaweed becomes 58 of many kinds-even candy, and ice cream - as well as medicine. Believe it or not, fresh water is another 59 from the sea. We cannot drink ocean water. Some of its contents may. 60 illness. But ocean water becomes fresh water when the salts are 61 . In the future, we will find ourselves 62 more and more on fresh water from the sea. The sea63us food, fertilizer, minerals, water, and other gifts. What do we give the sea? Garbage. We pollute the ocean 64 we use it as a garbage dump. Huge as it is, the ocean cannot hold all the water that we pour into it. 65 garbage into the ocean is killing off sea life. Yet as the world population grows, we may need the sea and its gifts ,more than ever.请在第___________处填上正确答案．
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