阳沟

例句：

1. 1. The sewer system is designed to carry away wastewater from the city.
   这个下水道系统设计用来将城市中的废水排出去。
2. 2. The construction of this new sewer will improve our city's drainage system.
   这座新下水道的建设将改善我们的城市排水系统。
3. 3. The old sewer was filled with garbage and stagnant water, making it a breeding ground for disease.
   旧的下水道里堆满了垃圾和死水，成了疾病滋生的温床。