现在完成时是过去做了一个动作持续或影响到了现在,过去式是过去做了一个动作和现在无关.
You have a nice watch.--Thank you.My father___(send)it to me on my birthday.
sent
The house was very expensive and it____(cost) us over forty thousand yuan.
cost
How beautiful your garden is!--Yse.My father____(grow)some flowers in it.
has grown