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honest; upright; decent; proper; respectable; straight; serious; sensible
彼の話をまともに信じる人は少ない。
Few people take his stories seriously.
忙しくてまともに食事をとる時間がない。
I am so busy that I do not have time to eat a proper meal.
まともな理由がないのに会議を欠席した。
He was absent from the meeting without a valid reason.