medium length hole的用法和樣例：
例句
- Test Research on Parameter Optimization for Long and Medium Hole Drilling and Blasting in Sanxin Co.
三鑫公司中深孔鑿岩爆破參數優化與試驗研究。 - As a result,the short hole shrinkage method with flat bottom structure was employed to mine the stope firstly,then stoping ore pillar by medium length hole caving method.
后溝金礦採用平底結構淺孔留礦法先採礦房，後用中深孔崩落法回採礦柱，經兩年多的生產實踐，取得較好的技術經濟指標。
