a water butt的用法和样例：
- A water power station must have a dam.
- Every apartment house has a water tank on its roof.
- The water butt catches the overflow from this pipe.
- The police used a water cannon on the rioters and soon brought them to heel.
- Yes. And also a water polo match.
- Around the engine cylinder is a water jacket.
a water butt的相关资料：