Ключевые слова: activity, big, career, coal, coalfield, construction, development, dig, digger, diging, dirt, dragline, dredger, earth, ecology, environment, equipment, excavate, excavator, exploration, gear, heavy, industrial, industry, large, limestone, machine, machinery, metal, mine, mineral, mining, mover, open, ore, pit, quarry, resource, rock, site, sky, steel, stone, technology, work,