Ответы
1. Ride a horse; watch TV; do sports; go to the cinema; play computer game; practice playing the piano; take part in a concert; surf the Net; go for a walk; join the club
2. 1) many
2) too
3) enough
4) enough
3. 1) too
2) mustn't
3) enough
4) too
5) mustn't
6) too
7) enough
8) must
9) too
10) mustn't
11) must
4. 1) My favourite subject is Math and PC
2) After school I like to do some exercises for get fit my body
3) After school I do my homework, watch videos on YouTube
4) I surf to the Internet so much time, and I know that don't healthy but it's so difficult put your phone on table
5) first rule: ask your parents before you register in other sites
second rule: don't click in unfamiliar link
third rule: don't tell anyone where you live
fourth rule: if you receive a message for unfamiliar person - don't answer