Exercise 13. put the verb to be in the plural and change the sentence accordingly: 1. i am always glad to see them. 2. when is he free? — he is free in the evenings. 3. she is so happy! 4. when is he at home? — he is at home in the morning. 5. who is ill? — my mother is. 6. are you hungry? — no, i am not. 7. is your sister at school? — no, she isn’t. she isn’t at school. 8. who is away? — petrov is away. 9. am i right? — yes, you are. 10. how are you? — i’m quite well, thank you. 11. are you tired? — yes, i am. 12. there is a woman in the room. 13. who is absent? — ivanov is. 14. i am thirsty. 15. she is wrong.