a substance that things can be made from 原材料◆building materials (= bricks, sand, glass, etc.) 建筑材料◆recycled materials 再生材料◆They produce insulating materials for the electrical industry. 他们生产电力工业用的绝缘材料。
things that are needed in order to do a particular activity 材料◆cleaning/packaging materials 清洁／包装材料
written information, ideas, etc. used for a particular purpose 资料；素材◆The company produces its own training material. 这家公司自编培训教材。◆marketing/promotional materials 营销／促销资料
bill of materials collateral material direct materials raw material