If you ever get a mouthful of ocean water, you’ll find it’s very salty. How

游客2024-02-15  15

问题 If you ever get a mouthful of ocean water, you’ll find it’s very salty.
    How did it get this way?
    Rivers are the oceans’ saltshakers. Almost every river in the world finally【S1】______its waters into an ocean. While the river is running【S2】______the sea, it loosens some of the land and carries it along. The land is made up of rocks and soil, which【S3】______minerals. One of these minerals is salt.
    You can’t taste the【S4】______in river water because the river doesn’t carry much salt at any one time. And you can’t taste it in most lakes because as one river brings a little salt in, another river carries it【S5】______. It bas taken rivers millions and millions of years to pour【S6】______salt into the oceans to make ocean water taste salty.
    Salt water is not good for people to【S7】______. It is not good for plants. We can’t stop the rivers from carrying salt from the land to the sea, but we can do something so that we can use the waters of the【S8】______for people and plants.
    Scientists are working on machines that will take salt out of ocean water. Some of these machines work very well, but they【S9】______too much to use as much as we would like. So the scientists keep trying to find cheaper【S10】______to do the job. The people and plants on the land of this Earth need nonsalty ocean water more than gold and jewels!

A salt            B ocean           C enough            D towards
E taste           F ways            G cost              H pours
I contain         J out             K river             L involve
M sea             N salty           O drink [br] 【S8】

选项

答案 M

解析
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