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
이 연구에서는 대조군과 실험군을 비교했습니다.i yeongueseoneun daejo-gun-gwa silheom-gun-eul bigyohaessseubnida.In this study, we compared the control group and the experimental group.