On January 17, he wrote, "Enjoying your #vacation? Please be cautious of fine dust!! Wearing a mask is a must!!"

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Meanwhile, Joo Won is taking a break from his military service at the 3rd Infantry Division. He is scheduled to be discharged in February of 2019.

It's good to see he's doing well!

#?? ? ??? ???? ??!! ??? ??!!

A post shared by ?? (@zu.won_moon.jun.won) on Jan 17, 2018 at 12:23am PST