Zhè shì xìngmìng-yōuguān de dàshì, yìdiǎnr yě bù néng mǎhu.
This is a matter of life and death, so we can't be the least bit careless.
Tips
usage
Means the same as 生死攸关, which is more common. Both follow the pattern X + 攸关 "X is at stake": 性命 is "life", so a life hangs on it. 利害攸关 works the same way with interests.
