second order subroutine

例句：

1. 1.The second-order subroutine is responsible for the calculation of the product.
   二级子程序负责计算乘积。
2. 2. The software developer needs to write a second-order subroutine to solve this problem.
   软件开发者需要编写一个二级子程序来解决这个问题。
3. 3.The second-order subroutine was used to optimize the performance of the system.
   二级子程序被用来优化系统的性能。