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
서울의 과밀학구에서 학생 수가 너무 많아 수업이 어려워요.Seoul-ui gwamilhakgu-eseo haksaeng suga neomu manha su-eob-i eoryeowoyo.In the overcrowded school district of Seoul, there are so many students that classes are difficult.