1, that is, around the theme of your paper, you will elaborate from many aspects, and the subtitle is based on the overview of each aspect, so that readers can see the structure of your paper clearly and play the role of prompting the content to attract readers.

2. For example, an essay entitled "Motherly love" has three subheadings, which express this topic from different aspects, namely "warm love", "severe love" and "kind love". You don't have to write a subtitle, you can decide for yourself according to the content of the article.