问题补充：people usuaiiy piant trees in spring every year怎样改为被动语态 最佳回答：The trees was usuaiiy pianted in spring every year。 其他回答：
问题补充：people usuaiiy piant trees in spring every year怎样改为被动语态
最佳回答：
The trees was usuaiiy pianted in spring every year。
其他回答：
