Clearly communicating the timeline of your research to the reader is extremely important, and depends on your using the proper verb tense in writing your manuscripts. Verb tense indicates whether the action of a sentence occurred in the past, present, or future, and helps to organize the flow of your writing and outline the sequence of events to emphasize your point.
<We can help with your writing. See our services.>
Verb Tense Writing Tips

In any scientific manuscript, sequence and timeline are important. For example, your experiments precede your summary of the results and outcomes. Your methodology precedes your experiments, as its concepts inspired the experiments. Further, the work of other scientists likely preceded your current work and discussion of these previous findings adds dimension to your manuscript. In addition, if you are attempting to show instances of cause and effect, it’s important to note what came first and what subsequently resulted.
- Using correct verb tense clarifies the timeline of your research and process.
- Incorrect verb tense can confuse the reader about the sequence of your arguments.
- In the English language, there are 12 verb tenses.
Simple | Progressive | Perfect | Perfect Progressive | |
Present | I investigate | I am investigating | I have investigated | I have been investigating |
Past | I investigated | I was investigating | I had investigated | I had been investigating |
Future | I will investigate | I will be investigating | I will have investigated | I will have been investigating |
The present tense shows that an action is taking place in the present, but does not indicate when the action will end. You may also choose to use the present tense to describe a fact that is universally true and not limited to a particular time, as seen in the following quote:
Infected hosts differ in their responses to pathogens; some hosts are resilient and recover their original health, whereas others follow a divergent path and die.1
The past tense shows that an action was completed in the past, while the future tense shows action that is yet to be completed–more of a prediction than a statement of finished reality. You can see in the example below that the researchers used past tense to discuss their proposed thesis, and then the future tense to highlight its predictions.
We started (past tense) with the proposition that infected patients will trace (future tense) a path over a multidimensional manifold in disease space; resilient patients will travel (future tense) predictable paths as they sicken and recover, and patients who do poorly will also take (future tense) predictable paths when they sicken and die.1
In science manuscript writing, there are standard practices regarding which verb tense to use for each section of the manuscript.
The Abstract will usually contain a mixture of verb tenses, as the background is generally based on published findings, which are presented in the present tense; the methods, results, and conclusion are presented in past tense.
The Introduction is your explanation of the previous findings that led to your question. Because the Introduction mainly discusses previously published research that is currently accepted as fact, these findings are presented in the present tense. For example:
Rheumatoid arthritis is (present tense) a common autoimmune disease primarily manifesting as chronic synovitis, subsequently leading to a change in joint integrity. Progressive disability and systemic complications are (present tense) strongly associated with a decreased quality of life.2
In the Introduction, you may also use a mixture of past tense and present tense to indicate why you are performing your research. For example:
Pain relief is (present tense) a major goal in the treatment of RA, but is only partly achieved (past tense) by NSAIDs or opioids.2
Methods and Results, on the other hand, are always written in past tense because you are describing what you have done and what resulted. Figures and Table legends are referred to in the present tense.
Figure 1 shows….
The Discussion will include a mixture of tenses as you discuss previous findings (present tense), your findings (past tense), and present your plans for further studies (future tense). Using the correct verb tense will eliminate confusion regarding what was known before your study and what your study has added.
Verb tense errors can distract readers from the value of your manuscript’s content. Choose the right tense to clearly communicate your research. Change verb tenses only when there is a real change in time. When you are writing about actions that take place in the same timeframe, be sure to keep using the same tense for all of the verbs associated with those sentences. By aligning your writing with these simple guidelines, you can ensure that you are communicating clearly to your readers.
References
- Torres BY, Oliveira JHM, Thomas Tate A, Rath P, Cumnock K, Schneider DS. Tracking resilience to infections by mapping disease space. PLoS Biology 2016; 14(4): e1002436.
- Meier FM, Frerix M, Hermann W, Muller-Ladner U. Current immunotherapy in rheumatoid arthritis. Immunotherapy 2013; 5(9):955-974.