用一般过去时
I really had a meaningful vacation. I tried to finish doing my homework as soon as possible so that I could have lots of spare time. I spent three days with my grandparents and helped them do some housewokk. I also visited my old friends and went to to the park with them. Besides, I learnt how to play tennis and it was really cool. What's more, I reviewed my lessons , prepared new lessons and read some interesting books. What a wonderful vacation I had.
一般将来时： I will visit my grandparents and stay with them for about three days. I am going to visit my old friends and go to the park with them. Of course, I will finish doing my homework on time and prepare for the new lessons. I am going to read some interesting books, surf the internet and go to movies. I am sure I will have a happy vacation.