Given that the ground rules to establish and maintain traceability are simple, it seems hard to understand why a lot of projects abandon traceability along the way.
已知建立并维护追溯关系的基本法则很简单，那么似乎很难理解的是，为什么大量项目一直放弃追溯。
2
Under the follow-on contract, Harris of Melbourne, Fla., will manage, maintain and repair the system’s ground equipment and software.
根据合同内容，哈里斯公司将管理、维护和维修系统地面装备与软件。
3
The Light is love and if you can maintain your place as a channel for it, you will be helping to ground it upon Earth.