We can write a sentence in two different ways. We can do it by using the verb to indicate whether the subject performs an action (active voice) or receives the action (passive voice). We usually write active sentences. Why we want to write passive sentences is explained in Part 4.

The verb is in the active voice when the subject,which can be a person or thing performs the action

  • Cats ate the fish. (Subject: cats; verb: ate: object: fish)

The doer of the action is the cats. The verb ate is in the active voice and is followed by the object.)


The verb is in the passive voice when the action is done to the subject.

  • The fish was eaten by cats. (Verb: eaten; subject: fish)

In this passive sentence, the subject is the fish. The subject in the active voice cats now becomes the object of the verb eaten.

As can be seen, changing the active sentence into a passive voice causes the subject to become the object, and the object become the subject. The verb phrase used in the passive sentence is the verb to be followed by the past participle of the verb. The passive verb follows the tense of the active verb. For example, if the active verb is in the simple present tense, the passive verb too is in the simple present tense.


Only verbs that take on an object (transitive verb) can be a passive verb.

  • He runs away.
  • The sun shines brightly.
  • The boss feels tired today.

Each of the above three sentences does not have an object, so it’s not possible to convert them into passive sentences.

In the passive sentence, we use the preposition by to be followed by the object. We use it to show who or what does or has done the action. We can omit by and in most cases, it does not affect the clarity of the meaning of the sentence. We use it when we think it is necessary.