A period of time as reckoned from a specific date serving as the basis of its chronological system.
A period of time as reckoned from a specific date serving as the basis of its chronological system.
年代从某一具体日期算起的一段时间，也用作其年代系统的根据
A period of time as reckoned from a specific date serving as the basis of its chronological system.
年代从某一具体日期算起的一段时间，也用作其年代系统的根据