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confidence; trust; faith; reputation
credit
彼の言うことを信用しないほうがいいよ。
You shouldn't trust what he says.
信用は一度失うと取り戻せない。
Once you lose trust, you can't get it back.
長く付き合ってこそ、本当の信用が生まれるんだ。
Real trust only comes from a long relationship.