Составить 3 отрицательных предложения и 3 дополнительных с глаголом to be!

I'm not writing now. She isn't cooking now. He isn't a teacher.
I'm writing now. She's cooking now. He's a teacher.

L am not happy
the book is not interesting
He is not our teacher
l am not a doctor
l am not in the room
the book is not in the table