经济发展理论研究的是经济系统如何产生不断改变它的力量。
The theory of economic development is the study of how the economic system generates the forces which incessantly transform it.
地理学是研究地方的科学。它的视野宏大，视角全景。
热闹的场合可以锻炼心境，安静可以养心，坐时可以守心，行动时可以考验心灵，言时省心，动时制心。
力气单薄就不要去背负重物，说话没分量就不要规劝别人。
Music has the power to heal, to inspire, and to bring people together.