Вставить глагол to be y Present Simple. 1) ... they at home? - No, they... not at home,...

Question

Вставить глагол to be y Present Simple.
1) ... they at home? - No, they... not at home, they... at work.
2) My brother .... a worker. He ... at work.
3) ... you an engineer? - Yes, I ... .
4) ... your sister a typist? - No, she ... not a typist, she ... a student.
5) ... your brother at school? - Yes, he ... .
6) ... your sisters at school? - No, she ... not at school.
7. My sister ... at home.
8. ... this your watch? - Yes, it ... .
9) She ... an actress.
10. This ... my bag.
11) My uncle ... an office worker.
12) He ... at work.
13) Helen ... a painter. She has some fine pictures. They... on the walls. She has some fine pictures. They ... on the walls. She has much paper. It ... on the shelf. The shelf. The shelf ... brown. It ... on the wall. Helen has a brother. He ... a student. He has a family. His family .... not in St. Petersburg, it ... in Moscow.

Answer 1

1) ARE they at home? - No, they ARE not at home, they ARE at work. 
2) My brother IS a worker. He IS at work. 
3) ARE you an engineer? - Yes, I AM. 
4) IS your sister a typist? - No, she IS not a typist, she IS a student. 
5) IS your brother at school? - Yes, he IS. 
6) ARE your sisters at school? - No, she IS not at school. (в вопросе почему-то мн.ч, а в ответе-ед.ч?)
7. My sister IS at home. 
8. IS this your watch? - Yes, it IS. 
9) She IS an actress. 
10. This IS my bag. 
11) My uncle IS an office worker. 
12) He IS at work. 
13) Helen IS a painter. She has some fine pictures. They ARE on the walls. She has some fine pictures. They ARE on the walls. She has much paper. It IS on the shelf. The shelf. The shelf IS brown. It IS on the wall. Helen has a brother. He IS a student. He has a family. His family IS not in St. Petersburg, it IS in Moscow.
"TO BE" в  Present Simple
I=am
He,She,It=is
We,You,They=are