sunk manhole cover

例句：

1. 1. Theworker had to dive under the sinking manhole cover to fix the leak.
   工人不得不潜入沉没的井盖下修理泄漏。
2. 2. The old building was covered in moss and needed a new sunken manhole cover.
   这座老建筑长满了苔藓，需要一个新的沉没式井盖。
3. 3. They used a special tool to lift the sunken manhole cover and access the damaged sewer line.
   他们使用一种特殊工具来抬起沉没式井盖，以进入受损的下水道管线。