Active Voice

Instructors often tell students to write in the active voice. What does this mean? Active voice emphasizes a subject doing something, as in the following sentence:

Captain Hawes fired the gun.

I made a mistake.

Passive Voice

By contrast, passive voice emphasizes something done to a subject.

The gun was fired.
A mistake was made.

Passive voice emphasizes a different subject: in the examples above, passive voice places the focus on gun and mistake, while active voice places the focus on who fired the gun and who made the mistake.

Passive voice can also leave out important information—who did the action—contributing to vagueness and evasiveness.

Active or Passive Voice?

In general, use the active voice because it is usually more direct, provides more
information, and reduces wordiness. Passive voice often requires more words than active voice to express an idea, thus contributing to the problem of wordiness.

Active: Captain Hawes fired the gun.
Passive: The gun was fired by Captain Hawes.

Active: The President made a mistake.
Passive: A mistake was made by the President.

However, use the passive voice when you want to emphasize the receiver rather than the doer of the action:

Passive: Tetracycline was increased to 50 mg.
Active: Researchers increased tetracycline to 50 mg.

Passive: Students in Klein's (2003) study were paid $25 to participate.
Active: Klein (2003) paid students $25 to participate in the study.

Use passive voice to avoid awkward and vague pronouns (like the pronouns you and we , when they don't refer to identified individuals):

Active: You can use fewer words, but you will lose important information.
Passive: Fewer words can be used, but important information will be lost.

In the last example, passive voice removes the the vague subject, you, and places the emphasis on what can be done, rather than who can do it.