longitudinal underdrain

例句：

1. 1. The longitudinalunderdrain system is designed to preventwater from seeping into the foundation.
   纵向排水管系统设计用来防止水分渗入地基。
2. 2.The construction of the longitudinalunderdrain was completed ahead of schedule.
   纵向排水管的施工提前完成。
3. 3. The longitudinal underdrain was installedin the basement to prevent water damage.
   在地下室安装了纵向排水管以防止水损害。