Ключевые слова: bore, cave, cavern, construction, dark, dig, digging, discovery, drill, driller, drilling, engineering, equipment, excavation, exploration, explore, export, extract, extraction, fossil, geology, gold, industrial, industry, machine, machinery, mine, miner, mineral, mining, modern, operation, processing, production, resource, rock, stone, technology, treasure, tunnel, tunneling, underground, vehicle, work,