Question

9. David has been painting/has painted in his studio since 10 o’clock.

10. Mary and Sam have collected/ have been collecting stamps for 3 years.

11. Their parents have been/have being friends since their childhood.

12. Dave has been/ has been being a student for 2 years.
Present Perfect

Answer 1

9. David has been painting in his studio since 10 o’clock.

10. Mary and Sam have been collecting stamps for 3 years.

11. Their parents have been friends since their childhood.

12.Dave has been a student for 2 years.