free fall weir

例句：

1. 1.The engineer designed the free fall weir to control the flow of water during floods.
   工程师设计了自由落体堰来控制洪水期间的水流。
2. 2. The free fall weir was a crucial component in the flood prevention system.
   自由落体堰是防洪系统的关键组成部分。
3. 3. The construction of the free fall weir required careful planning and execution.
   自由落体堰的建设需要仔细规划和执行。