There's a List of "25 Handy Words That Simply Don’t Exist In English" going around. A lot of those words seem more esoteric than handy to me, so here are three I'm more likely to use in day-to-day conversation.
Übermorgen - the day after tomorrow
Vorgestern - the day before yesterday
Doch. - The word "doch" kann have several meanings, but the one I'm thinking of is to give a positive answer to a negative question. If someone answers "Don't you like strawberries?" with "yes", do they mean "yes, you're right", or "yes, I do like strawberries"? "Doch" is an unambiguous one-word answer meaning "you're wrong, I do."
What's a word in another language that you wish English had? Or what's a concept you'd like to have a specific word for?
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