normal operation curve

例句：

1. 1. The normal operationcurve of the machine is crucialfor its performance.
   机器的正常操作曲线对其性能至关重要。
2. 2. The engineer adjusted the normaloperation curve to improve efficiency.
   工程师调整了正常操作曲线以提高效率。
3. 3. Thenormal operation curve was usedto predict the machine'sperformance under different conditions.
   正常操作曲线被用来预测机器在不同条件下的性能。