My sister is at home. 
We are not at school. We are at home.
My brother is a pupil. He is at school. 
Is your mother at home No, she is at work. 
Is your cousin at home No, he is at school. He is a pupil.
Is your sister a teacher No, she is a student. 
Is your father at work No, he is at home. 
Is your sister a typist Yes, she is. Is she at home No, she is at work. 
My grandfather is a scientist. 
My mother is not a teacher. She is a doctor. She is a very good doctor.