Annotation is to explain the content involved in the paper outside the paper, and its purpose is to let readers better understand the content in the paper. Annotation is an integral part of academic papers, not something outside the article.

For example, the ghost of Hegel haunts Marx's works. After praising Hegel for discovering "the correct law of dialectics", Marx immediately criticized Hegel for putting forward dialectics in the form of idealism and mysticism. 1858, he wrote to Engels that Hegel's logic was very helpful to his method of analyzing Das Kapital, but Hegel made dialectics very mysterious.

Note: 1868, he wrote to Kugman, saying that his explanation method was different from Hegel's because he was a materialist and Hegel was an idealist, but once the mysterious form of Hegel's dialectics was stripped away, his basic form of dialectics remained.

There are three forms of annotation: brackets, footnotes and endnotes.

Parentheses are placed in the middle of the text where comments are needed, and there are few comments. When the text is short, you can use parentheses.

For example, the formation and evolution of granite has always been controversial, namely the famous granite and granite (read, 1948).

Community refers to the traditional social life with human feelings and sense of identity based on blood, geography, emotion and natural will (Toennies 1999).

Footnotes separate the text with a horizontal line at the bottom of the page, and write notes below the horizontal line. Footnotes are for the convenience of readers to compare and check in time when reading.