From the first section to the third section , it illustrates the evolution of the federal role in elementary and secondary education a nd reveals the developmental characteristics in each period from the era before independence to now according to the time order . the fourth section is the analysis of the federal role in elementary and secondary education 第一节至第三节是按照时间的先后顺序，阐述了美国建国前的殖民地时期、建国至二战前、战后至80年代联邦政府基础教育职能的发生发展的演变过程以及80年代以来的联邦政府基础教育职能的新发展。
In section ii , " historical development of american teachers " continuing education " , historical development of american teachers " continuing education is carded . the author summarizes and analyses its characteristics and its developmental causes in three historical stages , including its rising in 1850s , its growth during the period from 1850s to world war ii and its further development from world war ii to the present 在第二部分“美国教师继续教育的历史发展”中，梳理了美国教师继续教育历史发展历程，总结了殖民地时期到19世纪中叶以前、 19世纪中叶至二战前、二战后到现在其兴起、发展及进一步完善三个不同历史阶段的特点，分析了其发展的原因。
