Figure 2: The storage structure of a piece of history news. Remark: The useful elements in this paper are: NewsID , Date , Title , CSN , Area , KP , Text , CommentsUser , in which CommentsUser shows the user list of whom comments this news article, CSN denotes the class and sub-class ID of this news article (e.g., CSN   =  02.15 means that class ID is 02 and sub-class ID is 15), and KP is the named entity of type person which will be discussed in Section 4.2.