医院必须确保供电系统是绝对关键的任务，因为病人的生命依赖于它。

The hospital must ensure the power supply system is ___mission-critical, as patients' lives depend on it.

在手术过程中，麻醉师的任务是至关重要的。

During the surgery, the anesthesiologist's role is ___mission-critical.