What is the difference between the active and the passive voice?
Before we discuss when the passive voice might be preferable to the active voice, let's look briefly at the basics of identifying both constructions.
The Passive Voice
In a passive construction, the object of an action becomes the subject of a sentence. That is, the person or thing carrying out the action isn't the grammatical subject of the sentence. Consider this passive sentence;
The TV was turned on by Agatha.
Agatha is carrying out the action (the subject), and the TV is being acted upon (the object), but in this sentence, the TV is in the position where you would expect to find the grammatical subject, creating a passive voice.
The Active Voice
If we take the same sentence but give it an active construction, the result is as follows;
Agatha turned on the TV.
Agatha is the subject (the actor) and is in the appropriate position in the sentence structure. The sentence becomes clearer, more emphatic and has forward momentum.
This is a rudimentary explanation of the active and passive voices, but serves to demonstrate that the active voice is usually better.
However, the passive voice is sometimes preferable...
Here are five instances when the passive voice can be justifiably used to good effect.
1, To give emphasis to the receiver of the action.
When the object (or receiver of the action) is perceived as more familiar or of greater importance, place it in the position of the subject.
The following sentence is active, but gives emphasis to the abstract 'millions of people'.
Millions of people have read 'To Kill A Mockingbird'.
It would be better, in this case, to give emphasis to the more specific, more familiar, and ultimately more important, 'To Kill A Mockingbird', like so;
'To Kill A Mockingbird' has been read by millions.
So the active voice would be preferable for a paragraph that was about the readers, but if the book is the subject of the paragraph, use th passive voice.
2, To de-emphasise the performer of the action.
To de-emphasise the performer of the action, use the truncated passive voice. It is particularly useful for imparting information about an action that has been taken, where the person or people who carried out the action are of little interest to the reader.
For example, the following sentence uses the active voice;
Our engineers have installed more powerful internet to provide faster connection times.
But does the customer really care who did the job, as long as it was done? In this situation, the better sentence construction might be passive;
More powerful internet connection has been installed to provide faster connection times.
3, To avoid responsibility
The diplomatic passive voice is useful when we want to avoid placing blame.
The active construction places responsibility with a particular person;
David mistreated the employee.
Whereas the passive voice is more general, and allows for the writer to convey the information without placing blame on an individual;
The employee was mistreated.
4, To create smooth transitions
It is sometimes necessary to use the passive voice to smoothly link sentences. If we constantly use the active voice, it can become jolting and unnatural to the ear.
5, To maintain a consistent point of view
If you begin by using the passive voice (for any of the above reasons), it is usually wise to maintain a consistent voice.
If we want to avoid naming the subject and use the passive voice, like so;
Our practises have been reviewed and found to be excellent.
It would be inconsistent to follow it up with a sentence in the active voice, such as;
We should convey this.
It would be much better to stick with the passive voice to maintain a consistent point of view;
Our practises have been reviewed and found to be excellent. This should be conveyed.