极限 (jí xiàn): limit; extreme boundary

The bridge's load-bearing capacity has reached its limit; adding any more weight could be dangerous.

In the last five kilometers of the marathon, he felt his physical strength had reached its limit, but he still persisted and finished the whole race.

This country's oil production is already approaching its limit, and it's difficult to increase it significantly.

Her limit for enduring pain is three hours; beyond that, she must take painkillers.