downward mining

例句：

1. 1. The company is engaged in downward mining operations in the area.
   该公司在该区域从事向下挖掘作业。
2. 2.The miners are working underground to mine for minerals.
   矿工们在地下工作，开采矿物。
3. 3.The engineers were tasked with designing a system for downward mining.
   工程师们被指派设计一个用于向下挖掘的系统。