type of manhole

例句：

1. 1.The manhole was covered with a layer of mud.
   那个下水道盖被一层泥覆盖着。
2. 2. The workers had to dig out the manhole and repair it.
   工人们不得不挖开这个井盖并修理它。
3. 3. The manhole was filled with water, making it difficult to access.
   这个井盖被水填满了，使得难以接近。