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The guest lineup on this episode with Cha Tae Hyun as the official 4th MC included Lee Yoon Ji, Jung Si Ah, Kim Ji Woo, and Jung Joo Ri. Lee Yoon Ji answered the MCs' questions about why she'd become interested in idols as of late, that it was because she liked to watch tv while taking care of her newborn baby. 

She named Kang Daniel as the idol she currently has her eyes on, then went on, "I got curious because I was asked to guest on 'Radio Star'... In truth, originally... (Turns to Cha Tae Hyun) Sunbaenim I'm sorry, I like you very much, but that MC position is originally..." 

Before she could continue, Kim Gu Ra pointed at Cha Tae Hyun and demanded, "She wants to know why you're sitting there when this position is for an idol!" Lee Yoon Ji apologetically continued, "With sunbaenim, I can see him on productions all the time, but I don't come out on variety shows a lot..." 

How did Cha Tae Hyun react? With a sour expression, he joked, "Well [the staff] should've told me in advance too, that the guests were all ahjummas today." 

Check out the clip from today's broadcast above!