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　　Many new problems have appeared in our modern life．One of the biggest of every country is pollution．In America, there are laws to keep the air and water pure and clean．These are new laws and it has taken much time to clean a polluted river or lake．Now the fish are healthy again and people can enjoy swimming in clean water．When food is brought from the grocery store(杂货店)to the home, it is packaged in paper, glass tin, or plastic．Every day a newspaper comes to the home．Americans used to put all these materials in the garbage bag which is packed up by a large truck．The truck takes these materials to a garbage(垃圾)dump(堆)or land fill．The truck dumps the garbage into a large hole and land is pushed over the garbage　until the hole is filled．Then, a new hole must be found．

　　As the years go by, the garbage increases as the pollution grows．Scientists suggested that some garbage could be used again．They suggested four ideas to businessmen who could make money by recycling or using paper, glass, tin, and plastic again．

　　Now, a recycling truck comes to each home once a week to pick up the materials．American families collect their newspapers in a box and clean all glass, tin, and plastic．The truck takes them to a factory for recycling．The newspaper is ground up into very small pieces and made green, brown, and clear mostly．The glass is crushed(捣，碾)and made into new glass．The tin is cleaned and melted so it can be made into new tin cans．The plastic is melted down so it can be used to make new container．

　　Recycling is a way to save the environment from pollution by using many materials again．

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