subfluvial tunnel

例句：

1. 1. The subfluvial riverbed is home to a variety of plant and animal life.
   亚河床是各种植物和动物生活的家园。
2. 2.Subfluvial sediment transport is an important process in river erosion.
   亚河床沉积物输送是河流侵蚀过程中的一个重要过程。
3. 3. The subfluvial tectonic activity is responsible for the formation of many mountain ranges.
   亚河床构造活动是形成许多山脉的原因。