The special adjective тћт 'that,' when used with не, means 'wrong, not the one intended'. Put prepositions between не and тћт e.g. не в тћт инститџт 'to the wrong institute'.
— ТІ прочитђла урћк на сегћдня? "Did you read the lesson for today?"
— Дђ, нћ ї, кђжется, прочитђла не тћт урћк. "Yes, but I seem to have read the wrong lesson."
— Ђ ї, кђжется, пришёл не на тџ лљкцию. "And I seem to have come to the wrong lecture."