My favourite exercise

请以“My favorite exercise”为题写一篇英语短文，词数不少于70。内容可自行发挥，但须包含以下要点：

1. What is your favorite exercise?  

2. Why do you like it?

3. How often do you do it?

学生习作:

My favourite exercise

There are many different kinds of sports, such as running, playing basketball and so on. I like swimming best. I began swimming when I was ten years old. My brother is good at swimming and he taught me to swim. I felt very relaxed and happy. We also joined a swimming club. We usually go swimming twice a month. After I do the exercise, I always feel very relaxed. Since I began swimming, I have become stronger and healthier.

I like swimming very much and I hope I can become a professional swimmer one day.