hollow weir

例句：

1. 1. The hollow weir was designed to prevent floods inthe lowlands.
   这个空心堤坝的设计是为了在低地防止洪水。
2. 2. The engineershad to reinforce the hollow weir towithstand the heavy rains.
   工程师们不得不加固这个空心堤坝以抵御大雨。
3. 3.The hollow weir was a crucial partof the flood control system.
   这个空心堤坝是防洪系统的关键部分。