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to keep; to preserve; to hold; to retain; to maintain; to sustain
to last; to endure; to keep well (food); to wear well; to be durable
健康を保つためには規則正しい生活が欠かせないよ。
Regular lifestyle is essential to maintain health.
室温を一定に保つことで快適に過ごすことができる。
You can stay comfortable by keeping the room temperature constant.
彼女は年齢を感じさせない若さを保っているようだ。
She seems to maintain a youthfulness that belies her age.