The past participles are formed by adding –ed to the base form of regular verbs (fire – fired, jump – jumped, move – moved) or by
adding other endings to the base form of irregular verbs (be – been; feel – felt, hide – hidden) as they do not end in –ed or by changing their spellings (fight – fought, see – saw, teach – taught). The past participle expresses a completed action in the past. It must come after the helping verbs or auxiliary verbs have (have, has, had) to form the perfect tenses in
the active voice or be (is, are, was, were) in the passive voice. When it modifies a noun,
it functions as an adjective and is known as a participial adjective.
Past participle used in the perfect tenses in the active voice.
Perfect tenses must use the past participle to follow the auxiliary verbs has, have and had.
Past participle used in the passive voice.
Only the past participle form of the verb can be used in the passive voice. The past participle must immediately follow an auxiliary verb. Both the auxiliary verbs and past participles are shown in bold
Past participle used as adjective.
A past participle functions as an adjective to modify a noun and is known as a participial adjective. It usually comes before the noun that it modifies. The following examples show participial adjectives in bold.