Thinking about the active and passive voices

Cherise Saywell

I’m a huge fan of the active voice and I spend a lot of time extolling its virtues. There are good reasons to prefer it: the active voice is generally clearer and more concise; it’s assertive and energetic. Shifting a sentence from the passive to the active voice can be revelatory for students who want to be more ‘present’ on the page, or who feel their academic writing lacks personality.

But I often encounter objections, especially (but by no means exclusively) from students of the sciences and engineering. They argue that the passive is the preferred voice of their discipline, journals require it and that the active voice is less scholarly or too subjective.

Active sentences

Scientific journals don’t necessarily require articles to be written mainly or entirely in the passive voice. Look at this famous example from Nature:

We wish to suggest a structure for the salt of deoxyribose nucleic acid (D.N.A.). This structure has novel features which are of considerable biological interest.[1]

James Watson and Francis Crick open their article with two active sentences. Does the pronoun make it subjective or not scholarly?

I’d be cautious about gifting the quality of objectivity to the passive style. But still, it’s understandable that students might not feel confident enough in their writing (or sufficiently established in their discipline) to choose the active voice.

Mixing active and passive

Rather than argue, I think it’s better to try a different approach. After all, if the passive style risks being hard to read, the same might be said of a piece written entirely in the active voice. Generally, we don’t use either style exclusively. Watson and Crick’s article is an often-cited example:

This is the sentence that follows their two active openers:

A structure for nucleic acid has already been proposed by Pauling and Corey.

It’s passive. I’ll come back to this.

Rather than thinking in an either/or approach to each style, it may be more useful to think about when to use the passive voice and how to avoid the common pitfalls.

When the passive voice is useful

1 When the actor in the sentence is unknown, irrelevant or obvious

Look at these examples:

• Up to 90% of the energy in light bulbs is wasted in the form of heat.
• Further extensions were made to this now-listed building in 1978 and 2004.

In the first example, it’s irrelevant what is doing the wasting. In the second, it may not be relevant who made the extensions. Making these sentences active wouldn’t improve them.

2 When the actor is less important than the action

In this situation, the passive voice redirects attention to the action or the object.

• The findings of this study will be publicised widely.
• The honey bees were kept overnight in a humidified chamber at room temperature.

If you really needed to know the actor, you could use the active voice:

• The research team will widely publicise the findings of this study.
• The researchers kept the honey bees overnight in a humidified chamber at room temperature.

3 For improving the writing flow

Sentences read smoothly when the agent (the person, thing or idea generating the action) is near the beginning. A key use of the passive voice is to switch the order of a sentence to put the object of the action first— like the honey bees in the passive sentence above.

Similarly, the third sentence in the Watson and Crick introduction is in the passive:

A structure for nucleic acid has already been proposed by Pauling and Corey.[2]

In the active voice, the third sentence would read:

Pauling and Corey have already proposed a structure for nucleic acid.

Why did Watson and Crick select the passive over the active for this particular sentence? Because they wanted the focus to be the structure (of DNA). The structure is the topic of the sentence, not Pauling and Corey. Also, referring to ‘structure’ at the start of the third sentence links back to the first two sentences and prepares the reader for the upcoming information. In this instance, choosing the passive made more sense.

Thinking about how and when and why you’re using the passive voice can make your writing more effective.

Pitfalls of the passive voice

However, you should be aware of the issues in using the passive voice.

1 It can be quite wordy.

Compare the following:
• If the passive voice is adopted, more words are often used.
• The passive voice often uses more words.

If you need to be succinct, the active voice is usually better.

2 It runs the risk of being ungrammatical.

Dangling modifiers are the main risk — sentences where it is not clear who is performing the action. (The purpose of a modifier is to give more information about the subject. When the implied subject doesn’t match the stated subject of the modified clause, we get a dangling modifier.) For example:

Having analysed all the data, the methodology was found to be fundamentally flawed.

It’s not clear who or what analysed the data — the structure of the sentence implies that it was the methodology. Here are two possible corrections:

Passive
When the data was analysed, the methodology was found to be fundamentally flawed.

Active
The researchers analysed the data but found the methodology was fundamentally flawed.

If you feel safer with the passive voice, or if you don’t want to rock the boat, consider how you might use it strategically. Allow yourself the occasional active sentence to liven up the writing, to keep things moving. Above all, make sure your passive sentences are clear and precise.