漫长的历史江河,浩渺的知识海洋,构成了庞大杂芜的信息群,引莘莘学子竞折腰,令芸芸师生叹史难。学生说历史好听难记。老师说学历史门好进难出。 The long historical rivers and the vast sea of ​​knowledge constitute a vast and mixed information cluster, which leads the students to compete and make the teacher’s life difficult. Students say history is hard to remember. The teacher said that studying history is difficult and difficult.