The QI Elves on Twitter opened a can of worms when they mentioned that the Irish language has no words for “Yes” or “No”. Dozens of tweets later saying that there are “Tá” and “Níl” or “‘Sea” and “Ní hea”, the Elves threw their hands up in the air and decided to leave the Irish alone.
While, strictly speaking, it is true that there are no words for “Yes” and “No”, in the Irish language to answer in the affirmative or negative, one repeats the verb of the asked question. For example, if one asks “Are you going to the cinema?” (An bhfuil tú ag dul go dtí an picturlann?) the answer is either “I am” (Tá mé) or “I am not” (Níl má).
This happens even when Irish people speak in English, and is part of the charm of Hiberno-English that everyone seems to love.