1. Hobby is what you in your free time
2. Playing the piano, playing the guitar, drawing, dancing, singing
3. Yes, I have a hobby
4. My grandma draws pictures, my friend likes to sing.
5. In my free time I usually draw or sing.
6. Yes, it's important to have a hobby, because:
Firstly: you always know what you can do in your free time
Secondly: you do self-development
Thirdly: it's fun
7. Yes, I know one: collecting weird stuff
8. Every hobby is interesting
9. Yes, I have collected stamps.
10. Yes. it can be a hobby too.