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sleeping face
彼の寝顔はとても愛らしい。
His sleeping face is very adorable.
母親は子供の寝顔をそっと見つめた。
The mother gently gazed at her child's sleeping face.
久しぶりに穏やかな寝顔を見て安心した。
I felt relieved seeing a peaceful sleeping face for the first time in a while.