1.Thise men are not doctors. Are those men doctors? Yes, they are/No,they aren't.
2.Kate is not a teacher. Is Kate a teacher?Yes,she is/No.she isn't.
3.The students are not in that room.Are the students in that room?Yes,they are/No,they aren't.
4.my friend is not a student.Is my friend a student?Yes, she (or he) is/No she (or he) isn't.
5.These books are not good.Are these books good?Yes,they are.No,they aren't