Why should people plant trees?

Why should people plant trees?的回答 why should we plant more trees? Why should we plant more trees 回答,用英语啊,我初三啊,谢谢哈 Why do people plant trees every year?——(keep) our air clean 改错误】1.She look young.2.Why are the people plant trees?3.Are 主动句变被动句1.People should plant more trees every year2.Children Why should we protect trees people often plant trees in winter why don't we go to plant trees this weekend we should plant more trees ,and..then the When should we plant the trees They (〉in spring. We should plant more trees to make the air_____.(clean)