Ответ:

1. I read books in the evening.

2. I don't read books in the morning.

3. I am writing an exercise now.

4. I am not writing a letter now.

5. They are playing in the yard now.

6. They are not playing in the street now.

7. Are they playing in the room now?

8. He helps his mother every day.

9. Does he help his mother every day?

10. He doesn't help his mother every day.

11. Do you go to school on Sunday? (?)

12. My friend doesn't like to play football.  

(My friend doesn't like playing football.)

13. I am not reading now.

14. Is he sleeping now?

15. We don't go to the country in winter. (?)

16. My sister eats sweets every day.

17. She isn't eating sweets now.

18. They do their homework in the afternoon.

19. They don't go for a walk in the evening.

20. My father doesn't work on Sunday. (?)

21. He works every day.​

Объяснение: