Tag questions and responses

You're George, aren't you?
-> Yes, I am. / No, I'm not. I'm Fred.
It's Tuesday today, isn't it?
-> Yes, it its. / No, it isn't. It's Monday.
Emma went abroad, didn't she?
-> Yes, she did. / No, she didn't. She stil here.

Walter isn't here today, is he?
-> No, he isn't. / Yes, he is. He's downstairs.
You aren't reading that paper, are you?
-> No, I am not. / Yes I am. You can have it later.
You don't know Sue, do you?
-> No, we don't. / Yes we do. We met last year.