fixed number testing

例句：

1. 1. The company conducted a fixed number of tests on the new product before releasing it to the market.
   公司在推出新产品之前进行了固定数量的测试。
2. 2. The engineers performed a fixed number of experiments to ensure the accuracy of their calculations.
   工程师们进行了固定数量的实验，以确保计算的准确性。
3. 3.The test results showed that the machine had a fixed number of moving parts, which made it easy to maintain and repair.
   测试结果显示，这台机器有固定的移动部件数量，这使得维护和修理变得容易。