论文部分内容阅读
一棵3米高、0.9米粗的树可以造5000张纸,可谁知道多少张纸能换一棵树呢?一个年仅14岁的小女孩却在默默地进行着这样一
A 3-meter-high, 0.9-meter thick tree can make 5000 sheets of paper. But who knows how many sheets of paper can be replaced by a tree? A 14-year-old girl silently carries out such a