trees have been planted to fix the sand

例句：

1. 1. The seeds were planted in the garden last week.
   上周，种子被种在了花园里。
2. 2. He planted a tree in his backyard to provide shade.
   他在后院种了一棵树以提供阴凉。
3. 3. The farmers have been planting rice for many years.
   农民们已经种了很多年的水稻。