Fill in the correct prepositions: at, on, to, in.
1. Berik isn’t keen ............ team sports, so he prefers to do athletics.
2. Exercising at a gym can be boring, but it’s worth it ............ the end.
3. Halima is hopeless ............ ball sports, but she’s a very good gymnast.
4. Drinking energy drinks can actually be harmful ............ your health.