There are four non-finite verb forms: infinitive, passive infinitive, and the two participles perfective/past participle and imperfective/present participle.
en.wikipedia.org More specifically, it consists of a noun or pronoun and either a past participle, a present participle, an adjective, or an appositive noun, all in the ablative.
en.wikipedia.org For example, imperfective verbs generally lack a past passive participle, while perfective verbs have no present participles.
en.wikipedia.org The present participle form of a verb may function as a noun, in which case it is referred to as a gerund.
en.wikipedia.org The three non-finite moods are the infinitive, past participle, and present participle.
en.wikipedia.org