Задание
Is "TO BE" main or auxiliary verb in the following sentences? Choose the correct variant.
I am taking a bath.
main
auxiliary
She is preparing dinner for us.
main
auxiliary
They have been studying all night.
main
auxiliary
I was given a free meal.
main
auxiliary
He was seen by fans at the airport.
main
auxiliary
This song has been sung by all nations.
main
auxiliary
They are fifteen years old.
main
auxiliary
They are not fifteen years old.
main
auxiliary
Are they fifteen years old?
main
auxiliary