When writing sentences, there are basically two ways to show action: passively and actively.
Passive: The ball was thrown to Brenna at second base.
Active: Reeza threw the ball to Brenna at second base.
Both sentences are complete and convey an action with the verb; however, the first sentence, the passive sentence, almost seems to be missing something. If you try to picture the action, you might see a baseball coming out of nowhere, hurtling toward a girl at second base. In the active sentence, the picture is more complete: you can see who threw the ball. Even with the additional information, both sentences are the same length.
In general, active voice is more effective.
Construct your sentences so that someone or something is doing something— not just something being done. Look for “to be” verbs like is, are, was, were. These are often a sign of passive voice.
That doesn’t mean passive voice can’t be useful. When you want to deemphasize the subject or avoid responsibility, passive voice is the way to go. For example, a car company that had a major mechanical issue with their airbags and had to recall millions of cars is probably not going to admit total fault.
An error was made in the production of the airbag in your Brand X car.
This is a useful application of passive voice. If the sentence were active, the company might actually be legally more liable.
Company X made a mistake in the production of airbags…
NO! Don’t say that. We’ll get sued!
Modifier errors caused by passive voice
Another problem with using passive voice is that it can cause grammatical errors like dangling or misplaced modifiers. A modifier is a descriptive word or phrase that often comes as a dependent clause at the start of a sentence.
With pinpoint accuracy, Reeza threw the ball to Brenna at second base.
The phrase “with pinpoint accuracy” is a modifier, describing how Reeza threw the ball. Now, try that same phrase with the passive sentence.
With pinpoint accuracy, the ball was thrown to Brenna at second base.
Now what is the phrase describing? From the structure of the sentence, the ball is throwing itself with pinpoint accuracy. In fact, the person who threw with accuracy isn’t even in the sentence, so this is a dangling modifier. Even if Reeza was in the sentence and the sentence was still passive, there would still be a logic problem.
With pinpoint accuracy, the ball was thrown by Reeza to Brenna at second base.
Now, Reeza is there, but the sentence still almost makes it sound like the ball was throwing itself. This is a misplaced modifier.
Correct modifier placement: With pinpoint accuracy, Reeza threw the ball to Brenna at second base.
More resources on passive and active voice and modifier errors:
“Active and passive verbs,” Oxford Dictionaries.
“Active vs Passive Voice,” Howcast. https://youtu.be/cOhUmttkt90
“Misplaced and Dangling Modifiers,” Tamu Writing Center.