usage and maintenance

• 使用与维修

usage and maintenance的用法和样例：

例句

1. I want to study the basics of design and maintenance of buildings.
   我想学习建筑设计与维修方面的基础知识。
2. Forging accessories primarily engaged in the production and sales, cement production and maintenance of equipment.
   主要从事锻压配件的生产与销售，水泥设备的生产与维修。