When the Klingon leader General Martok (who was recently elected to public office in New York) wishes you a merry Christmas, you should at least try to respond in his own language. There’s a limit to the Yuletide cheer that the universal translator can express.
Here is a handy guide to saying “merry Christmas” in 40 languages, including Farsi, Lithuanian and Korean.
Merry Christmas and Happy Holidays in Klingon:
QISmaS botIvjaj ‘ej DIS chu’ botIvjaj
And they forgot the Elvish version: