A：My father has bought some young trees.
B：Certainly! But why are you going to plant trees?
A：Why?
B：Oh, yes. I remember.
A：We must plant trees and flowers to make our world more beautiful.
B：  Where shall we meet?
A：At my home. You can help me take the trees.
B：All right. When shall we come?
A：At seven o’clock.
B：OK,