what is active voice?

The voice used to indicate that the grammatical subject of the verb is performing the action or causing the happening denoted by the verb; "`The boy threw the ball' uses the active voice".That is to say,active voice is a voice that indicates a subject has the semantic function of actor.

Example (English)
	The following sentence construction is in active voice. The subject Jones has the semantic function of actor. Jones built the house. The above active construction contrasts with the following construction in passive voice, where Jones has the semantic function of actor but house is the subject: The house was built by Jones.