Lee Changsoo, a board member of the Korean Association for Public Interpretation and Translation (professor at the Graduate School of Interpretation and Translation, Hankuk University of Foreign Studies), published English Expression Power-up Dictionary in October 2018, and the book became Darakwon’s 2019-2020 bestseller. Based on the vast amount of data accumulated from numerous translation experiences, he analyzed and systematically organized the reasons why Koreans keep making mistakes in certain English expressions, and he presented 17 principles that must be known for readers to speak like native speakers.