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face; mug
surface
cheek meat
そのつらを二度と見せるな。
Don't show that face of yours ever again.
あいつのつらを見ると腹が立つ。
It makes me angry just looking at that guy's mug.
よくそんなつらで人前に出られるものだな。
I can't believe you can show that mug of yours in public.