 It is formed by taking the infinitive stem and adding the ending "-в, -ла, -ло," and "-ли" to form the past tense participle (in reality the indefinite form of the adjective) and the ending "-лий" to form the regular adjective.An example of the adjectival form is "почорнілий".This participle is most commonly encountered as a gerund, while it is only used occasionally as an adjective.