The first-level title is the largest title, and the format No.4 is bold, single-line and punctuation-free, indicating the core of a chapter. The secondary title is the subtitle of the paper. The font size is the same as the text, with a single line and no punctuation at the end. Represents the branch field of this chapter.

The title is the eye of the article. The titles of various articles have many styles, but no matter what form, they always reflect the author's writing intention, theme and the core of the article in all or different aspects. Headings are generally divided into general headings, sub-headings and sub-headings.