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life and death; life or death
戦場では毎日が生き死にの瀬戸際だった。
On the battlefield, every day was a matter of life and death.
生き死にを共にした仲間との絆は特別なものだ。
The bond with comrades who shared life and death experiences is something special.
この手術は患者の生き死にに関わる重大な判断だ。
This surgery is a critical decision involving the patient's life or death.