Shorter descriptive abstracts usually take the form of a single paragraph, but longer informative abstracts are often structured, by which I mean that they are divided into shorter paragraphs. Each paragraph is dedicated to a particular aspect of the research and its implications. These paragraphs are sometimes marked with subheadings that match the headings used for the main sections of the paper itself. ‘Objectives,’ ‘Background,’ ‘Study Design,’ ‘Methods & Materials,’ ‘Results,’ ‘Discussion,’ ‘Conclusions’ and similar headings are therefore common in the abstracts of scientific research papers, but it is always best to check the publisher guidelines or ask your instructor about preferences before moving ahead with your abstract. Only once you know exactly what kind of paper and abstract you should be writing can you know exactly how to write an abstract for a research paper that will meet the requirements.