n.演练；钻孔
Mock drilling is a usual way in teaching of the major of management. 模拟演练是管理类专业教学中的常用方法。
After months of drilling, oil was found off the coast. 经数月钻探，在沿海找到了石油。
The workman is drilling in the wall. 工人正在墙上打孔。
