Economics is a science that studies

Economics is a science that studies the economy of the economic system" (Prasad K. N.)
"It is the science of a certain form of organization of human activities" (Knight F. N.).
Many other definitions have been offered for economics. Most focus on either the problems that economists usually deal with or the methods that economists use in dealing with these problems. So, economics can be defined as "the social science concerned with the problem of using or administrating scarce resources (the means of producing) so as to attain the greatest or maximum fulfillment of society's unlimited wants (the goal of producing)" (Prasad K. N.).
ECONOMY
The word "economy" signifies "organization" of people engaged in their main occupation of making a living" (Bain J. S.).
It is that social organization by means of which men satisfy their wants for scares goods and services. It is the sum of actions which make the satisfaction of wants possible" (Cassels J. M.).
"It is a system in which goods and services are produced with the ultimate object of satisfying human wants" (Stone R.).

Результаты (английский) 3:

经济学是研究经济体制”（Prasad K. N.）
”是科学的某种组织形式，人类活动”（骑士F N）。
许多其他定义了经济学。最关注的问题，经济学家通常处理的方法，经济学家使用在处理这些问题。所以，经济学可以定义为“有关使用或管理资源稀缺问题的社会科学（生产方式）达到最大或最大社会的无限希望（实现生产目标）”（Prasad K. N.）。
经济
“经济”意味着“组织”人们从事的主要职业谋生”（Bain J. S.）。
这是一种社会组织，它的意思是，人们能够满足他们的欲望，因为他们害怕货物和服务。这是笔的行动使满足需要的可能”（Cassels J. M.）。
”这是一个系统中，商品和服务都以满足人类欲望的终极目标产生“（石河）。