Поставьте следующие предложения во множественное число

1. This is a bird. 2. Is that also a bird? --No, it isn't. That is a cat. 3. Is that a good horse? — Yes, it is. 4. Is that cow big or small? - It is big. 5. This is an apple and that is a flower. 6. Where is the coin? It is in the box. 7. What colour is the box? - It is green. 8. What is it made of? - It is made of wood. 9. What is that man? - -He is a clerk. 10. Is he in the office? - -Yes, he is. 11. Is that woman a typist? --No, she isn't. - -What is she? — She is a doctor. 12. Is his brother at home? - Yes, he is. 13. This house has a balcony looking out on the street. 14. The architecture of this build­ing is quite modern. 15. This is a new district of St. Petersburg. 16. There is a shop, a cinema and a theatre in the new district. 17. He is a retired worker. 18.1 am a doctor. 19. We hear the sounds of a child's voice. 20. She is a nice girl.