English sentence‏‎s are mostly built using a simple pattern known as SVO‏‎ which stands for Subject + Verb‏ + Object‏‎:‎

{subject} + {verb} + {object}

Madeleine + broke + the wine glass.

The most important information in a sentence‏‎ usually comes at the beginning and in the examples above we’re interested in who broke the wine glass. This sentence is in the active voice‏‎.

However, sometimes we want to change the order of the information in a sentence.

Suppose we aren’t interested in who broke the glass (or maybe we don’t know). In that case we use the passive voice which puts the object‏‎ of the active sentence at the front of the passive sentence and the subject further down the line:

{object} + {verb} + by {subject}

The wine glass + was broken + by Madeleine.

Using the Passive Voice

Overall the active voice is much more widely used than the passive. It is easier to understand and clearer.

The passive voice, however, is used in writing‏‎ much more often than in speech. It can be found in newspapers and magazines or articles, and it is very common in scientific and technical writing.

The passive is particularly useful in two situations:

drawing attention to the object

When it is more important to draw our attention to the person or thing acted upon (i.e. the object) we use the passive voice:

My car was repaired.

Here we are not really interested in who repaired my car, the important thing is that it is now working and I can use it. Another example is this:

My car was stolen.

Here I am really concerned about the car and that’s my main worry so I’m telling you about the car first.

hiding the doer

But suppose we don’t know who did the action. By using the passive voice I can simply ignore the person(s) responsible for the action:

The glass was broken.

And I don’t know who did it. You can often see this kind of construction when a politician wants to hide the truth or someone does not want to admit they made a mistake:

Soldiers were sent into Afghanistan early last week.

The money was spent on frivolous office decoration.

Who ordered the soldiers to go in? Who spent the money? We will probably never know or never be told, but in the meantime the politician is telling us about what has happened, not the person who made it happen.

Forming the Passive Voice

The SVO construction is easy. To turn an SVO construction into the passive voice follow these simple steps:

1. Object > Subject

Make the object of the active sentence into the subject of the passive sentence:

active

{subject} + {verb} + {object}

Madeleine + broke + the wine glass.

passive

{object} + {verb} + by {subject}

The wine glass…

2. Passive Verb

Next, make the main verb passive; we do this by using be (conjugated in the same tense of the verb in the active voice) and the past participle of the main verb:

active

{subject} + {verb} + {object}

Madeleine + broke + the wine glass.

passive

{object} + {verb} + by {subject}

The wine glass + was broken…

3. Optional Subject

Optionally we can leave it like that and not include the subject:

The wine glass was broken.

However, we can also include the subject. In this case the subject of the active sentence, Madeleine, becomes the agent or doer of the passive sentence. The agent or doer is always introduced with by:

active

{subject} + {verb} + {object}

Madeleine + broke + the wine glass.

passive

{object} + {verb} + by {subject}

The wine glass + was broken + by Madeleine.

And that is it. These three simple steps turn an active sentence into a passive one.

Other Passives

Of course, being English, there are a few variations here. For example, sometimes you can make two different kinds of passive sentences if the original sentence has two objects‏‎.

active

{subject} + {verb} + {direct object} + {indirect object}.

The boy gave the stale cream cake to the teacher.

passive 1

{direct object} + {passive verb} + {indirect object} …

The stale cream cake was given to the teacher [by the boy].

passive 2

{indirect object} + {passive verb} + {direct object} …

The teacher was given the stale cream cake [by the boy].

N.B. When there are two objects (thing & person) we usually make the person the subject of the passive sentence (i.e. the last example).

Also, if the active sentence has an object clause‎, we can make a special kind of passive:

active

People think he was a genius.

passive1

It is thought he was a genius.

passive2

He is thought to have been a genius.

When someone does a professional service for us, we use the causative form‏‎. This form is also used to relate a bad experience:

I am having my car resprayed.

I had my wallet stolen.