поставьте предложения из вопросительной и отрицательной формы в опред. функцию глагола

1. He is a student now. - Is he a student now? - He is not a student now.
Is - глагол-связка, входящий в именное сказуемое.
2. She was ill last week. - Was she ill last week? - She wasnt ill last week.
Was - глагол-вязка, входящий в именное сказуемое.
3. I will be a doctor. - Will I be a doctor? - I will not be a doctor.
Will be - глагол-вязка, входящий в именное сказуемое.
4. The train is to arrive at 5. - Is the train to arrive at 5? - The train is not to arrive at 5.
Is to - эквивалент модального глагола must.
5. Im reading a book now. - Am I reading a book now? - I am not reading a book now.
Am - вспомогательный глагол, образующий время Present Continuous.
6. The house was built in 1986. - Was the house built in 1986? - The house was not built in 1986.
Was - вспомогательный глагол, образующий Past Simple Passive Voice.