Key difference: Passive voice means that the subject in a sentence is the receiver of the action. Active voice is when the subject in a sentence is the doer of the action.

As per English grammar, active and passive voices are both forms of writing and reading sentences. Both the voices are integral to lay emphasis, or to project energy into a piece of text. These are powerful tools available to a speaker/writer, through which he/she conveys a message across an audience and influences them. Active and passive voices are mainly dictated by the verbs used in them. These verbs are known as active verbs and passive verbs.

An active verb, or a dynamic verb is one which occurs over a period of time. It denotes an action that is progressive and evolutionary in nature. For example, words like to run, to go, to savor, etc. are active verbs. Stative verb, or a passive verb is a verb that stands for actions that are static in nature. These actions remain the same and do not change or evolve over a period of time. For example, love, hate, need, see, hear, etc. If a sentence uses an active verb, it is said to be in active voice. Whereas, a sentence comprising of a passive verb is known to be constructed in passive voice.   

Sentences that are constructed in a passive voice have their subjects as the receivers of the action performed, rather than the doers. This is because the verbs featuring in these sentences are passive in nature. Passive voice is sort of a roundabout way to describe something, rather than being direct, or voicing it actively.

For example:

An apple was eaten by Henry.

In this sentence, the word ‘apple’ is the subject, ‘eaten’ is the verb, and ‘Henry’ is the object. This sentence conveys the message that the subject ‘apple’ is receiving the action of being eaten by the object ‘Henry’.  The passive verb ‘eaten’ ratifies this fact, which enables the sentence to assume a passive voice.

The passive voice is generally not the recommended way of communicating things. This is because the passive voice is an indirect form of communication. It lacks directness and energy. Moreover, actively voiced sentences are concise and easy to understand, as compared to the passively voiced sentences. Actively voiced sentences are livelier in nature because they put the doer in a sentence first, and logically so. Whereas, in a passively voiced sentence the receiver gets promoted to the designation of the subject.

Having said that, the use of passively voiced sentences is regarded as a sensible alternative in situations such as:

When the doer of the action is unknown:

The lights were left on.

[You don't know who left them on.]

When the doer of the action is less important than the receiver:

The package was delivered this morning.

[It doesn't matter who brought it.]

When the doer of the action is someone you don't want to name:

I was given the wrong directions.

[You don't want to blame anyone in particular.]

Active voice, as the name suggests, is active or direct in nature. It is a more energetic sentence construction as compared to the passive voice. In sentences formed in active voice, the subject is always the doer of the action. Or, in other words, there is always an active verb featuring in such a sentence.

For example:

Henry ate an apple.

In the sentence above, ‘Henry’ is the subject, ‘ate’ is the verb, and ‘apple’ is the object. This sentence describes that the subject ‘Henry’ is the doer of the action of eating an apple. Since, this information is directly validated by the active verb ‘ate’, this sentence is in active voice.

Thus, actively and passively voiced sentences should be used appropriately as per the demands of a situation.

Comparison between Active Voice and Passive Voice:

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