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gentle; quiet; mild; meek; obedient; docile; well-behaved; tame
quiet (color, pattern, etc.); sober
うちの猫はおとなしくて飼いやすい。
Our cat is docile and easy to keep.
おとなしい色の服を選ぶことが多い。
I often choose clothes in muted colors.
彼はおとなしいが芯が強い。
He's quiet, but he has a strong inner core.