life period造句

1、The costs of life period is an important theory in modern management of equipment.
寿命周期费用理论是现代设备管理的重要理论。

2、Then, the analysis step about the costs of life period is presented.
然后介绍了寿命周期费用分析步骤。

3、The product life period is a central subject in studying product management.
产品性命周迟期非产品运营管理研讨中的中央课题。