Помогите пожалуйста с упражнением!! Очень нужно!!

1. This flat is clean. This is a clean flat. These flats are clean.

2. Are these his pencils? – Yes, these are his pencils.

3. This book is red. This is a red book. That book is not green.

4. Is Minsk a big city? – Yes, Minsk is a big city.

5. My flat is in Minsk and his flat is in Kiev.

6. This is an interesting book. This book is interesting.

7. This is a delicious melon.

8. This book is black. It is bad.

9. This is a hat. This hat is black. This is a black hat.

10. This bags are white. These are white bags.

11. This is a pen. This is a black pen. This pen is black.

12. This is a bag. This is my bag. This bag is not black.