把下列英语句子改为否定句，一般疑问句，肯定回答句，否定回答句

1.This is not my ruler, Is this your ruler? --Yes,it is /No,it isn't
2.My brother is not a student, Is your brother a student?--Yes,he is /No,he isn't
3.Mike and Amma are not students. Are Mike and Amma students?--Yes,they are/No,they aren't.
4.I am not a doctor. Are you a doctor?--Yes, I am/No, I am not.
5.He is not my brother. Is he your brother?--Yes,he is /No ,he isn't.
如果帮到你，请记得采纳，O(∩_∩)O谢谢

This is not my ruler .
Is my brother a student ？
Yes，mike and amma are students .
No，I‘m not a doctor .