shunt signal aspect

例句：

1. 1. Theengineer designed a new duct to improveairflow in the factory.
   工程师设计了一个新的管道来改善工厂的气流。
2. 2. Theconduit was used to transport heavymaterials through the tunnel.
   这个导管被用来通过隧道运输重材料。
3. 3. Thesiphon was used tocollect rainwater from the roof.
   这个虹吸管被用来从屋顶收集雨水。