First, the MCs said to John Park suspiciously, "Your English is bad," then they moved their attention to Kangnam, who introduced himself in Japanese. When TWICE's Sana then introduced herself in Japanese, the MCs said, "Now that's the real thing," next targeting Kangnam's language speaking skills.
Sana jumped on board, telling Kangnam, "I don't think your Japanese is that good. You speak with a Korean accent." Kangnam insisted, "I'm good at Japanese," but Sana simply said, "You're my senior in variety, but I think I'm your senior in Japanese," causing laughter.