五、补全短文
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,to feed millions of people.(1)We take minerals from the ocean.One way to get salt is to place seawater in a shallow basin and leave it until it evaporates.(2)Much gold and silver drift dissolved in the waters of the sea,too1.But the sea does not give them up by simple evaporation.Other gifts from the sea are pearls,sponges and seaweed.Pearls become jewelry.(3)Seaweed becomes food of many kinds 一 even candy,and ice cream — aswell as medicine.Believe it or not,fresh water is another gift from the sea.We cannot drink ocean water.(4)But ocean water becomes fresh water when the salts are removed.In the future，we will find ourselves depending more and more on fresh water from the sea.
The sea gives us food,fertilizer,minerals,water,and other gifts.What do we give the sea?Garbage.(5)Huge as it is,the ocean cannot hold all the water that we pour into it.Dumping garbage into the ocean is killing off sea life2.Yet as the world population grows,we may need the sea and its gifts more than ever.
We are finally learning that if we destroy our seas，we might also destroy ourselves.Hopefully,it is not too late.
注释：
Much gold and silver drift dissolved in the waters of the sea,too.还有不少金和银的漂流物溶解在海水里。
Dumping garbage into the ocean is killing off sea life.把垃圾往大海里倾倒就是在把海洋生物杀绝灭尽。
练习：
A.Natural sponges become cleaning aids.
B.We pollute the ocean when we use it as a garbage dump.
C.The area of the sea is becoming smaller and smaller.
D.Along with salt,other minerals are left after evaporation.
E.We even use their bones for fertilizer.
F.Some of its contents may cause illness.
答案与题解：
1.E前面二句讲了我们从大海捕捉大量的鱼供人们食用，这句接着讲“甚至连鱼的骨头也被 用来做化肥”。Even这个词在这里清楚地表示了这两句话的关系。
2.D这句话的前一句讲的是我们可以通过水的蒸发从海水中得到一种矿物质——盐，这句话 则说除了盐之外，水蒸发以后还有别的矿物质留下来。
3.A前面讲到除了矿物质外，大海还给了我们珍珠、海绵和海草这三样东西。接着作者分别 用一句话来说明每一样东西的昂途。先讲了珍珠，最后讲的是海草，所以这中间的一句应该 是讲海绵的用途了o
4.F前一句话说了^们不能喝海水，这句话解释了为什么不能喝，很自然。
5.B前面一句话用garbage—词有力地回答了“我们给予大海什么”这个带有自责性的问题,这句话则是对这个简单回答的具体解释。
