Mun-hee is so annoyed by Hae-mi who always acts like she knows best and tries to lecture her. As Hae-mi makes her look bad even in front of her own friends, Mun- hee whines about it to Soon-jae. But even Soon-jae says it is her fault and makes Mun-hee cry. Min-jeong decides to take firm measures against her students as they don’t take her seriously. However, even as she raises her voice and uses physical punishment, things just keep getting worse… (thetvdb.com)