A question tag is a grammatical structure that is added to the end of a sentence to turn it into a question. It is also known as a tag question or a question tail. A question tag typically consists of an auxiliary verb and a pronoun, which are used to confirm or clarify what has been said. For example, in the sentence “You’re coming with us, aren’t you?” the question tag “aren’t you?” is added to the end to confirm whether the person being addressed will be coming with the speaker. Question tags are often used in informal speech to seek agreement or confirmation from the listener.