His formal education ended after middle school, but he went on to start his own successful business.

formal 的意思是"正式的、正规的"，指按照官方或标准程序进行的。 education 来自拉丁语 educare（培养、教育），指"教育、培养"的过程或体系。 formal education 指"正规教育"，即在学校等教育机构中系统接受的教育，区别于自学或非正式学习。