Exercise 1. Insert the verb to be in the Present Simple:
1.1 Не ... a student. Не ... a good student.
1.2 His father ... a doctor.
1.3 My mother ... not a teacher.
1.4 ... your sister a pupil? – Yes, she ... .
1.5 They ... at home now.
1.6 This ... my house.
1.7 ... they at school? – No, they ... not at school.
1.8 ... your father a pilot? – Yes, he ... .
1.9 Nick ... not a student. He ... a pupil. He ... at school now.
1.10 These men ... drivers.
1.11 My friend ... an engineer. He ... at work.
1.12 ... your parents at home? – No, they ... not.