We use echo questions to show interest or surprise. For this purpose, the listener makes a short
question using the auxiliar or helping verb of the statement the speaker has just said.
S: She is visiting relatives at this moment.
L. Is she?
S: They bought a new Television set last week.
L. Did they?S: I live in the centre of New York.
L. Do you?
S: Alan´s got a job as a lifeguard.
L. Has he?
These short questions are used to check information. We use a positive statement followed by a negative tag when we expect the answer YES.
E.g. "You are American, aren't you?"
We use a negative statement followed by a positive tag when we expect the answer NO. E.g. "They haven't arrived yet, have they?"
I told you, didn't I?
It'll be sunny tomorrow, won't it?
He can't dive, can he?
They don't eat meat, do they?
She cooks well, doesn't she?
I am slim, aren't I?