Notes On Active voice and passive voice - Introduction - CBSE Class 6 English Grammar
Active / Passive Verb Forms Sentences can be active or passive. Therefore, tenses also have "active forms" and "passive forms."  WHAT IS PASSIVE CONSTRUCTION? Many verbs have a passive form. The passive construction inverts the active word order to emphasize what happened, rather than who did it: Active: I repaired the computer. Passive: The computer was repaired by me. Notice three things about this transformation of active order into passive order: 1. The object of the active sentence —"the computer"— becomes the subject of the passive sentence. 2. The passive verb has two parts: a form of the verb "be" ("was") and the past participle of the main verb ("repaired"). Other forms of the verb "be" include these: am, is, are, were, have been, had been, will have been. Other examples of past participles (which are not the same as the past tense, even when they look the same!) include "seen," "shown," and "swum." 3. The actor is now part of a prepositional phrase ("by me"). Passive constructions let you omit the actor altogether: Passive: The computer was repaired.

Summary

Active / Passive Verb Forms Sentences can be active or passive. Therefore, tenses also have "active forms" and "passive forms."  WHAT IS PASSIVE CONSTRUCTION? Many verbs have a passive form. The passive construction inverts the active word order to emphasize what happened, rather than who did it: Active: I repaired the computer. Passive: The computer was repaired by me. Notice three things about this transformation of active order into passive order: 1. The object of the active sentence —"the computer"— becomes the subject of the passive sentence. 2. The passive verb has two parts: a form of the verb "be" ("was") and the past participle of the main verb ("repaired"). Other forms of the verb "be" include these: am, is, are, were, have been, had been, will have been. Other examples of past participles (which are not the same as the past tense, even when they look the same!) include "seen," "shown," and "swum." 3. The actor is now part of a prepositional phrase ("by me"). Passive constructions let you omit the actor altogether: Passive: The computer was repaired.