system maintenance的用法和样例：
例句
- The security center does not give any system maintenance information and users had to look for those information in other places inside Control Panel.
安全中心并没有给任何系统维护，信息和用户不得不寻找这些信息在其他地方在控制面板。 - The system maintains an internal list that contains the child controls associated with a parent window.
系统维护包含与父窗口关联的子控件的内部列表。
