The abstract of the paper should be placed at the front of the table of contents. The purpose of the abstract is to let others know what your paper is about when they search, and there are keywords behind it to facilitate the search. It is not appropriate to make a long speech, but only introduce the background of the paper and what problems have been solved. What follows the table of contents is called "introduction" or "introduction". The trouble with many students is that they put everything that should be written in the introduction into the abstract.

_ Lu _ Ahong

_ lip sakura _ ttps://www . zhi Hu . com/question/40685 1307/answer/ 1339493883

_ Cong Chu Brown?

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