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to make war (on); to wage war (against); to go to war (with); to fight (with); to do battle (against)
to compete (against)
to struggle (against adversities, etc.); to fight; to contend; to resist
チームは最後まで諦めずに戦うことにした。
The team decided to fight until the end without giving up.
決勝で強豪チームと戦う。
Compete against a powerhouse team in the finals.
彼は病気と長い間戦っていたが回復した。
He fought against the illness for a long time but recovered.