SUBHEADINGS
1) Use subheadings to create structures that may include two or more paragraphs.
The principle of modularity suggests that each paragraph of a paper be self-contained and defend a single conclusion. However, papers often include arguments that require more than one paragraph to support. How can authors present and emphasize conclusions that apply to several distinct paragraphs?
Using subheadings can help to create structures that may include two or more paragraphs. Subheadings are single sentences that are commonly set apart from paragraphs and further emphasized by using bold or italicized text.
For example, subheadings may help to structure sections of a paper around hypotheses (Qiao et al., 2014; emphasis in brackets mine):
Turning performance was similar among inertia conditions [reject first hypothesis].
[Paragraph 1]
[Paragraph 2]
Peak braking forces did not decrease as predicted by the turning model [reject second hypothesis].
[Paragraph 1]
[Paragraph 2]
[Paragraph 3]
Force direction relative to the leg did not change with altered inertia [reject third hypothesis].
[Paragraph 1]
[Paragraph 2]
Just as for outlines and topic sentences, section headings are strongest if they are complete, conclusive sentences. Subheadings are the conclusions of arguments -- simply arguments that span multiple paragraphs. The topic sentences of the paragraphs in a section can be the premises that support the conclusion of the subheading.
Use parallel construction to help readers understand similar topics in different sections of a paper.
Parallel construction involves repetition of similar elements for emphasis and clarity (Strunk and White, 2000). Parallel construction can make both writing and reading easier. For writing, using a parallel construction can help in planning and outlining different sections of a paper. For example, if the Introduction is organized around defending three hypotheses (as in the example subheadings above), then the structure of the Introduction suggests a natural structure for the Results and Discussion: each can have three sections that correspond to the three hypotheses, in the same order as in the Introduction. Therefore, a parallel construction can help to organize and specify writing.
Parallel construction can also help the reader. For example, if a reader has a question about Hypothesis 2 in the Discussion section of a paper, with parallel construction the reader can easily find the data relating to Hypothesis 2 in the Results and justification for Hypothesis 2 in the Introduction. Parallel construction can therefore help both authors and readers communicate ideas.