USAGE

Question tags are little questions that people often use at the end of a sentence when talking. They can be used to make sure something is true/correct or to ask for agreement.

- You want coffee, don't you?
- You have seen the film, haven´t you?
- She's Irish, isn't she?

They are very common and useful because it is an easy and quick way to keep people's attention and force them to say something, so we can keep the conversation going.

- It's very cold today, isn't it?
- Oh yes, I think so.

FORM

You can only make a question tag using a special verb (modals and auxiliaries), so if the main verb in the sentence is a normal verb, then we use DO to make the question tag. But if the main verb is a special verb, we use that special verb for the question tag. The question tag will be in the same tense as the verb in the main clause.

- You like coffee, don't you?  (like: normal verb)
- You can help me, can't you?  (can: special verb)
- He is Mr Smith, isn't he ?
- They're making tea, aren't they?
- Your father will be there by ten, won't he?
- You've been to London, haven't you?
- Susan bought a new house,  didn't she?

We usually use an affirmative question tag after a negative sentence
- It isn't  very cold, is it?
- Mark can't speak French, can he?
- Your cousins didn´t come to visit us, did they?

And a negative question tag after an affirmative sentence
- It is very cold, isn't it?
- She likes this film, doesn't she?
- Your friend is going to come, isn't he?

And you must always use contractions in your question tags because a question tag without contraction sounds terribly pedantic!
- You are Tim, are you not?  (*#Ⱥʬʘᴟ₩҉ !!)

Note that we talk about affirmative or negative sentences, not necessarily verbs:

- You have nothing here, have you? ("You have nothing" is negative, so the question tag is affirmative.

MEANING

The meaning of a question tag depends on the intonation: A falling intonation is just looking for agreement, a rising intonation is a question, looking for confirmation or correction.

- Kelly will come later, won't she? ↗
- No, I think she won't come because she was feeling ill today.

- Kelly will come later, won’t she? ↘
- Sure, don't worry. She'll be here in a few minutes.

SPECIAL CASES  If you want to know about special cases and advanced usage, click here: Question Tags - Special Cases.

THE THREE BASIC RULES TO REMEMBER

❶ Question tags always use a special verb
❷ The subject is always a pronoun, and it is inverted (because it is a question, of course)
❸ Affirmative sentences add a negative question tag and negative sentences add an affirmative question tag

Is this too complicated for you when talking? Well, here are the good news: Native speakers often use a different kind of question tag, much more simple. In every case, they can always use RIGHT?, and that's good for every situation, so if you find it complicated, just use RIGHT? all the time and let natives do the other stuff:

- You want coffee, right?
- You have seen the film, right?
- She's Irish, right?

Note for Spanish speakers

Las questions tags son el equivalente al ¿no? etc. que se usan al final de muchas frases en español:

- You want coffee, don't you? =quieres café ¿no?
- You have seen the film, haven't you? =has visto la película ¿verdad?
- She's Irish, isn't she? =es irlandesa, ¿a que sí?

Cuando los hablantes de español hablan inglés, normalmente son incapaces de usar question tags, porque necesitan pensar mentalmente cómo construirlas en cada caso y no da tiempo, y porque el ¿no? sale automático, sin pensar. En ese caso, lo mejor es olvidarse de estas question tags elaboradas cuando uno habla y usar la que vale para todas las ocasiones: RIGHT? Sonarás igual de natural y evitarás el frecuente y desconcertante error de solar un ¿no? cada poco sin que un nativo entienda qué quieres decir con "We are friends, ¿no?" (me dice que somos amigos pero me dice que no, ¿en qué quedamos?)