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to attack; to destroy; to defeat; to conquer; to avenge
敵の城を伐つ計画が立てられた。
A plan was made to attack the enemy castle.
悪を伐つのが武士の務めだった。
It was a samurai's duty to defeat evil.
反乱軍を伐つために兵を送った。
Troops were sent to defeat the rebels.