Ключевые слова: apprentice, background, bench, change, craftsman, cutting, cylindrical, drain, equipment, foreman, gray, hacksaw, labor, man, metal, modify, multiracial, occupation, plastic, plumber, plumbing, precaution, pvc, safety, sanitation, saw, sawing, serious, smoking pipe, supervisor, support, tools, two men, waste, watching, water, work, workshop,