Active and Passive Voice.
Active Voice.
Active voice describes a sentence where the subject performs the action stated by the verb.
Tom threw a pie at Spike's face.
Here the verb threw expresses the action done by the subject, Tom. This sentence is in active voice.
Passive Voice.
Passive voice describes a sentence where the subject is acted upon by the verb.
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The ball was hit by Messi.
Here we see that something was done to the subject, the ball, by the verb hit. This sentence is in the passive voice.