Active and passive voice are both perfectly legitimate means of constructing a sentence. However, some publications, institutions, and instructors prefer the exclusive use of active voice. It is difficult to exclude passive voice without being able to recognize it.
What is the Difference Between Active and Passive Voice?
Many sentences in the English language contain what is known as an action verb, meaning that some action is being performed. In active voice, the subject of the sentence is performing the action of the verb. In passive voice, the action verb is acting upon the subject of the sentence.
Active: Researchers at the university conducted the brief study.
Passive: The study was conducted by researchers at the university.
While both sentences convey roughly the same idea, the researchers in the active voice sentence are doing the conducting. In the passive voice sentence, the action verb is acting on the subject.
Active: The fertilizer company polluted the river.
Passive: The river has been polluted.
In the first sentence, the fertilizer company was doing the polluting. In the second sentence, the polluting was done to the river.
Active: Jane completed her test.
Passive: The test was completed by Jane.
In the first sentence, Jane acts by completing her test. In the second sentence, the test is not performing an action.
When to Use Active or Passive Voice
If a publication or professor insists on the use of active voice, the decision to use active or passive voice is easy. However, there are some instances where style or clarity require a decision between the two.
If absolute clarity is required, active voice is usually considered more appropriate. Due to the changed relationship between the subject and verb, who or what is performing an action is not always clear in a passive voice sentence. This can cause confusion for the reader, and that is one of the reasons why many instructors prefer active voice. Additionally, active voice is more direct, which can convey a clearer understanding of the material being discussed.
The humanities may prefer active voice, but there are occasions when passive voice is more appropriate. For example, passive voice is helpful when the subject is unknown. If the writer or readers do not know the actor of the sentence, active voice might compromise clarity.
Technical writing is slightly different from writing in the humanities because technical writing often demands strict objectivity. Many authors in the scientific community prefer the use of passive voice and avoid first person writing for this reason. Active voice is still grammatically correct, but a stylistic preference might exist.
If the writing is for a publication, one of the best ways to determine a preference for active or passive voice is to view previous copies of the publication or the appropriate style guide.
The best way to learn to recognize active or passive voice is through practice and exposure. With time, writing in either voice will become automatic, allowing the writer to adjust his or her style for appropriate usage.