Question: Which South Korean actress appeared in both Gyebaek (2011) and Emergency Couple (2014)?
Sentence (from "Gyebaek (TV series)"): Gyebaek () is a 2011 South Korean period ("costume") drama series, starring Lee Seo-jin, Cho Jae-hyun, Song Ji-hyo and Oh Yeon-soo .
Relevant evidence: Yes