Write a letter to your friend talk about the activities you will do in this summer

I am very happy to receive your letter and invitation. Thank you for remembering that I wanted to travel somewhere this summer. I'm really looking forward to the activities we participate in in July.

In early July, I planned to visit my grandparents in the countryside with my family, so I'm sorry that I won't be able to attend your brother's birthday party. However, I'm completely free after that and camping sounds really fun so I'm excited if we can go together.

I've also thought of some activities we can participate in together. Do you want to take the opportunity to climb mountains while camping? I just learned about a beautiful place with fresh air and extremely suitable for relaxation.

If you are interested, please tell me. I will prepare well for our wonderful trip.