Tag questions are made up of a stem (statement) and a tag (short question form).
In opposite polarity tag questions, the verb in the tag and the verb in the stem have opposite values. Rising intonation on the tag indicates that the speaker is asking for information.
Rich will pay me back, won’t he?
You weren’t lying, were you?
Falling intonation on the tag indicates that the speaker expects the listener will agree with the information in the stem.
Sarah owns a car, doesn’t she?
In same polarity tag questions, both the stem and the tag are positive. A low pitch that jumps up on the tag and then falls indicates the speaker has reached a conclusion, which is stated in the stem.
So, that’s the reason you told him, is it?
Same polarity tag questions can also function as:
•an urgent imperative
Turn down the TV, will you!
•a polite request
Lend me your pen, would you?
Let’s stop for lunch, shall we?
You were supposed to pick me up at 5:00, remember?
•a request for feedback
You understand what I’m talking about, right?