depth of draining

例句：

1. 1. The depth of the river is about 20 meters.
   这条河的深度大约是20米。
2. 2. The water level in the lake is at its deepest point.
   湖中的水位达到最深处。
3. 3. The engineers were measuring the depth of the hole to ensure it was safe for mining.
   工程师们正在测量这个洞的深度，以确保它适合采矿。