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
음악에서 역진행은 멜로디가 반대 방향으로 움직이는 것을 의미합니다.eumakeseo yeokjinhaeng-eun mellodi-ga bande bangan-euro umjigineun geos-eul uimi-hamnida.In music, contrary motion refers to the melody moving in the opposite direction.