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influence; power; might; strength; potency; force; energy
その政党は選挙で勢力を拡大することに成功した。
That political party succeeded in expanding its power in the election.
台風の勢力が弱まって警報が解除される見込みだ。
The typhoon's power is weakening and the warning is expected to be lifted.
勢力争いが激化して組織内の雰囲気が悪化している。
Power struggles are intensifying and the atmosphere in the organization is worsening.