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to believe; to believe in; to place trust in; to confide in; to have faith in
彼の言うことを信ずることにしました。
I decided to take him at his word.
彼は最後まで仲間の無実を信じた。
He believed in his friend's innocence until the end.
私はこの計画の成功を信じている。
I believe in the success of this plan.