Scientists are trying to make the deserts into good land again. They want to bring water to the deserts so that people can live and grow food. Even so, more and more of the earth is becoming desert all the time.
Why Scientists think that people make deserts. People are doing bad things to the earth. Some people on the earth do not get very much rain. Yet, they still do not become deserts. This is because there are some small green plants growing there. Plants help keep water in the earth. Plants do not let the wind blow the dirt away. Without plants, the land can become a desert much more easily.
A man decides to make a farm in a very dry place. He digs in the earth and takes away the grass and plants that are already growing on the dry land.
He makes a farm. He puts plants in rows. The sun is very hot. It makes the land even drier. When the rain comes, it runs between the rows of plants. It washes the good dirt away. When the wind comes, it blows between
A. They keep the earth from becoming even drier.
B. They do not let wind blow the earth away.
C. They add color to the dry places.
D. They hold water.
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