Tag question

A question tag or tag question (also known as tail question) is a grammatical structure in which a declarative statement or an imperative is turned into a question by adding an interrogative fragment (the "tag"). For example, in the sentence "You're John, aren't you?", the statement "You're John" is turned into a question by the tag "aren't you". The term "question tag" is generally preferred by British grammarians, while their American counterparts prefer "tag question".

In most languages, tag questions are more common in colloquial spoken usage than in formal written usage. They can be an indicator of politeness, hedging, consensus seeking, emphasis and/or irony. They may suggest confidence or lack of confidence; they may be confrontational, defensive or tentative. Although they have the grammatical form of a question, they may be rhetorical (not expecting an answer). In other cases, when they do expect a response, they may differ from straightforward questions in that they cue the listener as to what response is desired. In legal settings, tag questions can often be found in a leading question. According to a specialist children's lawyer at the NSPCC, children find it difficult to answer tag questions other than in accordance with the expectation of the questioner using or tagging a question.

Question tags are formed in several ways, and many languages give a choice of formation. In some languages the most common is a single word or fixed phrase, whereas in others it is formed by a regular grammatical construction.

In many languages, the question tag is a simple positive or negative. Russian allows да? (yes) whereas Spanish and Italian use ¿no? and no? respectively. In Indonesian, sometimes ya? (yes) is used but it is more common to say kan?, which probably is a contraction of bukan (negation for nouns).

Another common formation is equivalent to the English correct? or the informal form right?. This more often is realised as the word for true or truth, such as in Polish prawda? , Slovak pravda? or the particle však?, or Spanish ¿verdad?, which in turn can be presented in a negative form, such as in the Polish nieprawdaż?, German nicht wahr? (not true) or Lithuanian ar ne?. Alternatively, a word or short phrase indicating agreement can be used, such as the French d'accord?.

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