填空题 A.consumer B.direct production C.commerce D.raw materials
E.making F.demand (noun) G.barter H.building
I.is concerned with
J.preserving

填空题 deals with
填空题 manufacturing
填空题 construction
填空题 keeping
填空题 customer
填空题 satisfy personal needs
填空题 trade
填空题 basic materials for manufacture
填空题 exchange
填空题 what can be paid for