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league; federation; union
各国が聯盟を組んで環境問題に取り組んだ。
Countries formed an alliance to tackle environmental issues.
労働者の聯盟が賃上げ交渉を開始した。
The workers' league began wage increase negotiations.
聯盟からの脱退を表明した国が相次いだ。
One country after another announced its withdrawal from the alliance.