阅读理解

　　It is said that another acre(英亩)of the world's forest will be destroyed forever．Why is this happening? There are two reasons－land and wood．In many countries the trees have been cut down because the land was needed for animals or crops．In other parts of the world the trees are cut down because their wood is wanted．This wood is used by local people for firewood or it is used for building．But many people don't know that in most places the trees won't be replaced．The soil in the forests is very thin, but it is protected by the trees．When the trees are cut down, the soil is washed away by the rain or blown away by the wind．Soon nothing can be grown on it．The forest becomes a desert．Then more land will be needed, and more trees will be cut down．

　　When the forest is destroyed, it isn't only the trees that are lost－the homes of millions of animals and plants are destroyed, too．All kinds of animals are in danger －fish，reptiles, birds, mammals, insects, and shellfish－as well as thousands of plants．

　　Who is to blame for this? The answer is simple：all of us．There are just too many people in the world．The world's population is now six billion．Of course, it's very easy to blame the local people．We don't cut down trees．They do．But the products are bought by people like you and me－wood houses, beds, tables, chairs, paper… Why are the forests being destroyed? Just look around．You are probably using it right now．

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