Papers usually have abstracts, some for international communication, and foreign language (mostly English) abstracts. It is a brief statement of the content of the paper, without comments or annotations. Other uses are to obtain necessary information without reading the full text of the paper. It should include the following contents: ① the purpose and significance of this study; (2) the main content of the study, which shows what has been done; (3) The basic conclusions and research results highlight the originality of the paper; ④ The significance of the conclusion or result. Although the abstract of the paper should reflect the above contents, the text must be very concise, the content should be fully summarized, and the length is generally limited to less than 5% of the words in the paper. For example, a 6000-word paper usually has an abstract of no more than 300 words. You can trace the paper network, and this website has an introduction to this.