深入·引人——我讲课的两点体会○陈铁军光阴似箭，岁月悠悠，我自上大学念历史系，毕业后在中学教历史，不想将要满二十年了。生也有涯，盛年难来，人一辈子能有几个二十年？回顾既往，自己还总算是在尽心尽力地学，尽心尽力地教，没有虚度日子，差可慰安。但这并不是说... In-depth·Introducing——Two points in my lecture ○ Chen Tiejun’s time flies. I have been studying history for a long time since I was in college. After graduating, I teach history in middle school. I don’t want to be 20 years old. There are also bounds to be born, and it is difficult to reach a happy age. Can people have a lifetime of several twenty years? Looking back on the past, I was still learning to do my best, and I tried my best to teach. I didn’t have to spend my days and I was relieved. But this is not to say...