Black Friday: lifetime access is on a special offer in the app, until November 30. Black Friday: special offer on lifetime access, until November 30. Download
대타론은 기존 이론을 대체하는 새로운 이론입니다.daetaron-eun gijeong ilyeon-eul daechi-haneun saeloun ilyeon-imnida.The substitute theory is a new theory that replaces the existing theory.