Dear Simon,
I was really glad to receive your letter. I hope that you really had a nice time in the mountains.
You ask me about my experience in doing extreme sports. Well, as for me I have tried parachute jumping twice this year. It was so exciting and unforgettable. I enjoyed my jumps very much. My parents are fond of extreme sports, so I don't have any problems with them. We like to spend our time doing different kinds of sport. By the way, I am going to try scuba diving this summer. It is said to be awesome and fascinating. Now I am finishing my letter and looking forward to getting a letter from you.
Best wishes,
Alex