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Упр.11.
1. We have a big dog. The dog is very clever.
2. My friend has a very good computer.
3. This boy is big. He is a student.
4. There is a very big piano in the hall.
5. This is a tree and that is not a tree. It's a bush.
6. I am a boy. I am a pupil. I go to school.
7. My sister is at work. She is a secretary. She works at a large office.
8. This is a very difficult question. I don't know the answer to it.
9. Do you see a little girl with a big ball in her hands? She is a pupil of our school.
10. There was a beautiful flower in this vase yesterday. Where is the flower now?

Упр.12.
1. There is a thick red carpet in my room. The carpet is on the floor in front of the sofa.
2. Where is the table in your brother's room? His table is near the window.
3. I can see a fine vase on the shelf. Is it your vase?
4. We have no piano in our living room.
5. My uncle is married. He has a beautiful wife. They have a son, but they have no daughter.
6. I can see a nice coffee table in the middle of the room to the risht of the door. It is black and red. I like the coffee table.
7. Our TV set is on a little table in the corner of the room.
8. There is a beautiful picture in my father's study. The picture is on the wall to the left of the window.    

Упр.13.
My aunt's flat is in a new house. There is a living room, a bedroom, a study, a bathroom and a kitchen in the flat. The bedroom is a large room with two windows. The room is light as the windows are large. There are white curtains on the windows. There are two beds with large pillows on them. There are small tables near the beds. There are lamps on them. To the left of the door there is a dressing table with a mirror on it. There is a low chair at the dressing table. There are several pictures on the pale green walls. There is a thick carpet on the floor. The carpet is dark green. The room is very cosy.