The past participle is the third principal part of a verb (after the base form and simple past).
Past participles can be regular or irregular.
a) Regular Verbs
Regular verbs form their past participle by adding -ed to the base form (the same as the simple past tense).
Examples: play → played → played
Most verbs: Add -ed
Examples: walk → walked
Verbs ending in -e: Add -d
Examples: love → loved
Verbs ending in consonant + y: Change y → i + ed
Examples: study → studied
One-syllable verbs ending in vowel + consonant: Double the consonant + -ed
Examples: stop → stopped
b) Irregular Verbs
Irregular verbs do not follow the -ed rule and must be memorized.
Examples: go → went → gone
a) Perfect tenses
Examples: I have eaten.
b) Passive voice
Examples: The book was written by her.
c) Adjective functions
Examples: The broken window needs repair.
d) Reduced Relative Clauses
Examples: The man who was arrested is my neighbor.
e) Participial Phrases
Past participles can introduce descriptive phrases.
Examples: Built in 1920, the house has historic value.