Language points:
19.. extend v. 伸展，延续
The hot weather extended into October. 炎热天气一直持续到10月份。
They extended the railway to the next down. 他们把铁路延伸到了下一个城镇
20. toil: (formal) n. hard work done over a long time. 苦工，长期的劳作
e.g. Many poor people had to suffer a life of toil. (许多穷人不得不一生辛苦)
21．occupy oneself with/ be occupied with : to be engaged or busy in doing 忙于…, 从事…
e.g. He often occupies himself with lots of meetings. (他经常忙于开会)
Doctor Higgins was occupied with a lab experiment when I found him. (我找到他的时候，希金斯博士正忙着做实验)
22. Nothing is spared to …
spare: v. 节省，限制性地使用。这句话的意思是“人们会不遗余力地把节日庆祝活动办的更加热闹欢快。”
e.g. They spare no expense in building the library. ( 他们斥巨资建造那座图书馆)
No effort is spared to solve that difficult problem. ( 我们会竭尽全力解决那个棘手的问题)
23. flourish: vi. (不及物动词) 繁荣，茂盛，兴旺
e.g. The plants flourish in warm climate. (温暖的气候下植物生长茂盛。)
Jazz flourished in the first decade of 20th century. ( 爵士乐在20世纪初开始流行)
24. supersede ：v. replace; substituted 取代；代替
e.g. The new deal supersedes the old agreement. (新的条约取代了旧的协议)
25 commemoration: n. 纪念 动词是“commemorate” 较为正式。
e.g. A 50th anniversary commemoration is planned for November. (一场五十周年的纪念仪式安排在11月举行)
The monument was built in commemoration of those who sacrificed their lives for the country’s independence. ( 这座纪念碑是为了纪念那些为国家独立牺牲的人们而建造的)