Treesareusefult的甄选

问题详情：短文填空请用适当的词完成下面的短文，每个空只能填写一个形式正确、意义相符的单词。Treesareusefultomaninthreeveryimportantways.Thefirstimportantwayisthattheyprovideman____1____food,woodandotherprod...