A good science paper follows a clear structure (introduction, materials and methods, results, and discussion) and is written in plain, precise language. This article explains each section and gives 7 pointers to keep in mind while you write.
Writing a good science paper is hard, but a clear structure and a few habits make it much easier.
The structure of a good science paper
Most science papers follow the same four main sections, often called IMRaD after their initials. Most journals also ask for a title, a short abstract at the start, and a list of references at the end.
Introduction
What problem were you trying to solve? Use the introduction to establish the context of your work and explain why it matters. Present the purpose of the study in the form of questions and a hypothesis. Also explain what was known and what was not known before the study, and how the study is expected to add to that knowledge.
Materials and methods
How did you solve the problem, and what materials did you need? Include all the relevant information about the objects you studied, then describe how you carried out the study. Order your sentences so that readers can follow the logical steps of your method.
Results
What did you find out? Present your key findings objectively, whether they are positive or negative. Your job here is to present the findings only. Save any interpretation for the next section.
To show your results as clearly as possible, use a combination of text, tables, and figures. Make sure that each table and figure presents different data.
Discussion
What does it all mean? Now is the time to interpret the key findings you described in the results section. Answer the questions and test the hypothesis you presented in the introduction.
Connect your key findings with what others have found, and explain any similarities and differences. Referring to other people's work also helps you interpret your results. Citations: how to do them properly explains how to credit them.
At the end of the discussion, draw a conclusion from your interpretation. Your conclusions must follow from the data in the results section. Never introduce new results in the discussion.
7 pointers to help you write a good science paper
Now that the structure is clear, here are some pointers that help you write a good science paper.
1. Use the right tense
Your work is done, so describe what you did and what you found (the methods and the results) in the past tense: We measured the height of each plant. Use the present tense for facts that are already established and for what your results show: These results suggest that light affects growth.
2. Use the active voice
Sometimes the passive voice is hard to avoid, especially in the methods section. Still, use the active voice whenever you can: it is shorter and clearer.
3. Limit each paragraph to one message
Each paragraph should cover only one topic. Most of the time, you present the main idea in the first sentence and use the following sentences to explain it.
4. Use short sentences
Short sentences are easy to read and understand. They get your point across more easily.
5. Avoid redundancy
Don't repeat a point just to stress its importance. Say it once, clearly.
6. Choose quantitative over qualitative
Give numbers instead of vague comparisons. Instead of "The seeds in group B germinated faster than the seeds in the control group", write "The seeds in group B germinated 5 hours earlier than the seeds in the control group."
7. Proofread your work
Read the paper aloud, or ask a colleague to read it, to find flaws and grammar mistakes. If you are not confident about your grammar, the Spell Checker marks spelling, grammar, and punctuation mistakes for you to review. For a longer project, see also how to write a research paper.