Participle is a special form of a verb. There are two types of Participles: Present Participle and Past Participle.

Present Participle is formed by adding ending -ing to the main verb:

• Examples: smile + ing = smiling, read + ing = reading

Past Participle of regular verbs can be formed by adding ending -ed  to the main verb. Past Participle of irregular verbs (sometimes called Verb 3 form) need to be memorized as they do not have a common rule.

• Examples: spoil + ed = spoiled, wear = worn

Present and Past Participles can be used as adjectives:

• a horrifying story
• a smashed window

When participles come after a noun, they are used like reduced relative clauses:

• I saw a man walking down the street. (I saw a man who was walking down the street.)
• I read a book written by O. Wilde. (I read a book that was written by O. Wilde.)