A Question tag is a type of Question form which is added to a statement to invite the listener's attention to the statement.
e.g.: You are Priya, aren't you?
In the above sentence the underlined part is the Tag question / Question tag and the preceding part is the statement.
* A Question tag is usually used in conversations.
* We use these question tags to ask if something is true or to ask somebody to agree with us.
* We do not put question tags after questions.
e.g.: Aren't you Priya, are you? - Wrong.
* Generally these are used with statements, commands, requests etc.
Some important points to learn to use question tags
1) If the statement is in the affirmative (positive), the tag is usually in the negative and vice versa.
e.g.: It's very hot, Isn't it?
affirmative Negative tag
* It is not very warm today, is it?
2. The short form n't is used in tag questions since tags are used in conversations.
3. If the statement has an auxiliary verb (helping verb), the same auxiliary verb is used in the tag.
e.g.: You haven't seen my wallet, have you?
4. The noun in the subject of the statement has to be replaced by an appropriate pronoun which agrees with it in number, gender and person.
e.g.: Fayaz is handsome, isn't he?
* Dhoni and Kohli are cricketers, aren't they?
5. In statements like - I'm late, I am playing well, I am beautiful etc., 'aren't I' is used in the tag.
e.g.: I'm late, aren't I?
I'm beautiful, amn't I? - wrong
I'm beautiful, aren't I? - Right
6. If the statement does not have an auxiliary, use do/ does/ did appropriately in the tag.
e.g.: Sundar sings well, doesn't he?
She laughed, didn't she?
They come here every day, don't they?
7. If a statement containing semi - negative words like little, few, hardly, scarcely, rarely...
is treated as a negative statement and take a positive tag.
e.g.: Venkatesh hardly ever goes to parties, does he?
8. Though 'few' and 'little' are negative, 'a few' and 'a little' are positive and therefore take a negative tag.
e.g.: A few people knew the way, didn't they?
9. A negative statement does not necessarily mean one with a negative verb. So long as there is a negative idea in it, it is a negative statement and takes a positive tag.
e.g.: None of the food was wasted, was it?
10. A statement containing 'used to' takes 'did' in the question tag.
e.g.: She used to play hockey, didn't she?
11. A suggestion that uses ‘let's’ (let us) uses ‘shall we?’ in the tag.
e.g.: Let's have a party, shall we?
12. With everybody, everyone, someone, somebody, we use the pronoun ‘they’ in the tag.
e.g.: Every one warned you, didn't they?
e.g.: Some one had recognized him, hadn't they?
13. Simple requests usually take 'will you', no matter what the verb, no matter whether it is a positive or negative request.
e.g.:Pass me the news paper, will you please?
14. Since ‘won't you’ suggests urgency, it is the form of the tag used with entreaties (earnest requests).
e.g.: Be careful when you cross the road, won’t you?