To protect his comrades, he acted without a thought for himself.
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From 司马迁's 《报任少卿书》 (Letter to Ren An, Han dynasty): 常思奋不顾身以殉国家之急 — 'I always thought of dashing ahead with no regard for my body, dying for the state's urgent needs.' Sima Qian was describing the loyal service he'd hoped his life would embody.
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High praise — reserved for genuine heroism: rescues, combat, disaster response. Don't use it for ordinary 'giving it your all' situations; that's 全力以赴.