Passive Form

On this page:
Why do we use a passive?
How do we make a passive?
Examples of passives: past, present, and future.

Why do we use a passive form?
Many English sentences use active verbs to say how the subject affects an object.
1A. The cat ate the mouse.
This sentence says that the subject, cat, did the verb, eat, to an object, mouse:
cat → eat→ mouse.
It makes the cat important.

What do we do if we want the mouse to be important? We use a passive form: mouse ← eat.

How do we make a passive form?
Example 1A. The cat ate the mouse.
To make a passive form of the same sentence, first, we move mouse to the start.
The mouse

Next, we change the active form into a passive form. To do this, we separate the active form into its tense (time) and its idea (meaning). We put the tense onto be, and we put the idea into past participle (the —en/ed/t form of a verb).

Because ate is the past tense of eat, we need the past tense of be, which is were for a (plural), or was for a (singular). Because mouse is singular, we use was.
The mouse was

Then, we add the —en/ed/t form of the meaning verb eat, which is eaten.
The mouse was eaten.

This sentence is now complete. It does not say who ate the mouse, but it does not need to. If we want to, we can add by and then the agent, who did the eating.
1B. The mouse was eaten by the cat.

This sentence now says the same thing as sentence 1A, but it makes the mouse important.

We always need to make sure the verb tense is the same in the active and the passive. If the active form is past, the passive form must be past; if the active form is future, the passive form must be future. If we change the tense, we change the thinking.

Example 2A. People in Italy make those shoes.
If we want to talk about those shoes, we first move those shoes to the start of the sentence.
Those shoes

Next, we use the present tense of be (because make is present), i.e., am, are, or is. Because those shoes are plural, we want to use are.
Those shoes are

Then, we add the —en/ed/t form of the verb make, which is made.
Those shoes are made

Because all shoes are made, this sentence is not useful, and the sentence 2A said where, so we can add that.
2B. Those shoes are made in Italy. ↔ People in Italy make those shoes.

Example 3A. Someone will paint the house tomorrow.
To make a passive form of the same sentence, first, we move house to the start.
The house

Next, because will paint is future, we need the future tense of be, which is will be.
The house will be

Then, we add the —en/ed/t form of the verb paint, which is painted, which looks like a past tense but is not a past tense. Most of the verbs in English use -ed for their past tense and for their past participle, but this sentence is future because the first part of the verb, will be, shows the time.
The house will be painted.

This sentence is now complete. It does not say exactly when, but it does not need to. If we want to, we can add the exact time.
3B. The house will be painted tomorrow. ↔Someone will paint the house tomorrow.

Remember, we always need to make sure the verb tense is the same in the active and the passive. Many students make mistakes with passives because they are thinking about how to organise the sentence, and so they forget to check the tense.

We can also use passives with perfect forms, to make perfect passives, with continuous forms, to make continuous passives, and with infinitives, to make passive infinitives, which are useful with modal verbs.

More examples
My car was stolen last night.
This play was written by William Shakespeare.

Many cars are stolen in this area.
These phones are made by Samsung.

Do not worry; your car will be found.
The first song will be sung by my friend.