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
도르래를 사용하여 무거운 물체를 쉽게 들어올릴 수 있습니다.doreuraereul sayonghayeo mugeoun mulcheoreul swibge deureoolil su itsseumnida.You can easily lift heavy objects using a pulley.