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to supplement; to make up for; to compensate for; to cover (a shortage, loss, etc.); to fill (e.g. a vacancy)
野菜不足をサプリメントで補うようにしている。
I try to make up for lack of vegetables with supplements.
チームの弱点を新しいメンバーで補うことにした。
We decided to make up for the team's weakness with new members.
お互いの欠点を補い合える関係が理想だと思う。
I think the ideal relationship is one where you complement each other's weaknesses.