auxiliary road

例句：

1. 1. The auxiliary power unit is responsible for providing backup power during emergencies.
   辅助动力单元负责在紧急情况下提供备用电源。
2. 2. The auxiliary light is a useful tool for illuminating dark areas.
   辅助灯是一个有用的工具，用于照亮黑暗区域。
3. 3. The auxiliary system helps to improve the efficiency of the main engine.
   辅助系统有助于提高主引擎的效率。