Ключевые слова: aluminum, big, coal, construction, copper, diamond, dig, digger, dirt, earth, ecology, environment, equipment, excavation, excavator, fuel, geology, gold, heating, heavy, helmet, hiking, industrial, industry, iron, landfill, loader, machine, metal, metallurgy, mine, mineral, nickel, open, overalls, people, pit, pollution, quarry, road, rock, sky, smoke, stone, transport, truck, uranium, work, worker,