"Mistakes were made." It is one of the most famous sentences in modern public life, and its power comes entirely from a grammatical choice.
The mechanics
In an active sentence, the subject performs the verb: The committee approved the budget. Three parts, all visible: actor, action, thing acted upon.
In a passive sentence, the thing acted upon becomes the subject: The budget was approved by the committee. The verb becomes a form of be plus a past participle, and the actor moves into a phrase beginning with by.
The important feature is that this phrase is optional. The budget was approved. The sentence is complete, correct, and silent about who did it.
When the passive is the right choice
The passive is not an error, and advice to "avoid the passive voice" is too blunt to be useful. Use it when:
- The actor is unknown. The window was broken during the night.
- The actor is irrelevant. The samples were heated to 60 °C. In scientific method sections the procedure matters and the person does not, which is why the passive dominates there.
- The receiver is the real topic. The manuscript was recovered in 1897 and has been housed in the national library ever since. Keeping the manuscript as the subject holds the paragraph together.
- You want to place old information first. English sentences read more smoothly when known information comes before new. The passive is a tool for arranging that.
When it hides something
Use the active when the actor matters and the reader deserves to know who it is.
Compare: Errors were made in the calculation with Our finance team made errors in the calculation. Both are true. Only one accepts responsibility.
Institutions, governments and companies reach for the passive at exactly the moments when a named actor would be uncomfortable: charges were filed, the decision was taken, your account has been suspended. Reading critically means noticing the missing by phrase and asking: by whom?
This is a question worth asking of your own writing too. Weak analytical writing is full of sentences like It is shown that the theme is developed. Shown by whom? Developed by whom? The poet develops the theme through repeated images of water names an actor and, in doing so, forces the writer to commit to a claim.
A practical routine
- Find the verbs in your paragraph.
- For each one, ask whether the sentence names who or what performs it.
- If it does not, ask whether that absence is deliberate.
- If it is not, rewrite the sentence with the actor as the subject.
Most writing improves. The sentences that survive step 3 are using the passive on purpose, which is the only good reason to use anything.