manhole with hanging cover

例句：

1. 1. The manhole was covered witha layer of dirt.
   那个地洞口被一层土覆盖着。
2. 2. They used to digholes in the ground for their children's toys.
   他们过去常在地里挖洞给孩子们玩玩具。
3. 3. Thehole in the wall ledto a secret room.
   墙上的洞通向一个秘密房间。