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
온도계에서 영점은 물이 얼기 시작하는 온도입니다.Ondogyeeseo yeongjeomeun muri eolgi sijakaneun ondoui imnida.On the thermometer, zero is the temperature at which water begins to freeze.