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
스타하노프제도는 노동 생산성을 높이기 위한 방법입니다.seutahanopheujedoneun nodong saengsanseong-eul nopi-gi wihan bangbeob-imnida.Stakhanovism is a method to increase labor productivity.