sewage pit

例句：

1. 1. The city has been working on cleaning up its sewage pits for years.
   这个城市多年来一直在努力清理其污水坑。
2. 2.The sewage pit was filled with a thick layer of scum.
   污水坑里堆满了厚厚的一层浮渣。
3. 3.The workers were digging into the sewage pit to find out what caused the problem.
   工人们正在挖掘污水坑，以找出问题的原因。