egg-shaped sewer

例句：

1. 1. The city's sewers are designed to handle the volume of wastewater.
   城市的下水道设计用来处理废水的量。
2. 2. The sewer system is a crucial part of our waste management system.
   下水道系统是我们废物管理系统中至关重要的一部分。
3. 3. The sewer was clogged with debris and had to be cleared manually.
   下水道被堵塞了，需要手动清理。