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当保罗还是一个小男孩的时候,他在犹他州的家附近有一个旧式的炼铜厂。从炼铜厂里排出的二氧化硫把原本美丽的森林变成了一片荒凉的废墟。一天,保罗家的一位小客人扫了一眼那片荒地,看见上
When Paul was a young boy, he had an old copper smelter near his home in Utah. Sulfur dioxide from the copper smelter turned the beautiful forest into a desolate ruin. One day a small guest at Paul’s home glanced at the piece of waste land and saw it