On this page:
Passive and active voice
Sentences can either be written in the “passive voice” or the “active voice”. Here are examples of each:
Active: Alexander Fleming discovered penicillin in 1928
Passive: Penicillin was discovered by Alexander Fleming in 1928.
In the active sentence, the person (subject) who made the discovery is placed at the beginning of the sentence. In the passive sentence, the object of the discovery is placed first.
One consequence of the passive sentence is that the person who made the discovery can be omitted entirely and the sentence will still be grammatically correct; but don’t use this approach as a tactic to cover up information you do not know!
Microsoft Word often highlights passive sentences as being incorrect. In academic writing this can usually be ignored as the passive voice is more acceptable.
Which voice should you write in?
Although the passive voice is considered the most formal writing style and is frequently used in academia, different disciplines have their own preferences, so you should check with your department.
For example, the sciences usually place greater emphasis on using the passive voice, but this is not universally true and has been changing recently in some areas. A good example of where the passive voice dominates in the sciences is in the reporting of research methods and results or experimental data, for example:
The solution was mixed thoroughly.
Stratified sampling was used to select interview participants
This approach is preferred in most cases because it focuses on what was done and what was found, rather than who did it. This also negates the requirement for a personal pronoun (where the identity of the person is of no consequence).