The notes of modern books are listed at the bottom of the main page of the text, called footnotes, also called personal letters. Footnotes should be added after the following text.

Footnotes are used as follows:

A definition is to explain a thing in the following way. Defining something is to reveal the sum of the essential attributes of this concept. When using the definition, we should consider the fluency of the article itself and other factors.

Second, for example. Although some technical terms are explained in the definition description, sometimes some readers still feel that they are too general and abstract and need to be explained more specifically with examples.

Third, classification description. In the academic field, we often have to face complex and diverse phenomena and a lot of materials. In order to make articles clear, we often need to use the methods of classification and explanation. The so-called classified description is a method of dividing a large class of things into several small classes and then classifying each small class to explain it. Master the standards and principles of classification when using.

4. Illustration is a method to explain things and phenomena intuitively with the help of nonverbal expression systems such as diagrams. This special way of explanation is widely used in academic papers, especially scientific papers. Of course, the chart description is also inseparable from the necessary text description, and the two should be organically combined. Charts should be concise and easy to understand, and the language should be concise.