Developed countries have traditionally maintained low tariffs on primary products and much higher tariffs on semi-manufactured and manufactured goods.
发达国家历来对初级产品保持着低关税，而对半成品和制成品保持着很高的关税。
2
Industry refers to manufacturing activities in making means of production, means of subsistence and processing semi-manufacturedgoods by making use of natural resources.
工业，是指采用自然物质资源，制造生产资料、生活资料，对农产品、半成品等进行加工的生产事业。
3
Material management deals with all material that is wanted by production, for examples work blanks, tools, semi-manufacturedgoods, finished product and waster.