11. My friend sometimes rides a bike in the park.
11. My friend is riding a bike in the park at the moment.
12. My friend often has dinner at McDonalds.
12. My friend is having dinner at McDonalds.
13. John and Brenda hardly ever do gym.
13. John and Brenda are doing gym now.
14. My mum never cooks pizza.
14. My mum is cooking pizza right now.
15. My dad washes his car every Sunday.
15. My dad is washing his car at the moment.

 rides
12. has dinner
13. does
14. cooks
15. washes
11. is riding
12. having dinner
13. is doing
14. is cooking
15. is washing