Non-Finite Verbs:
In linguistics,a non-finite verb (or a verbal) is a verb form that is not limited by a subject; and more generally,it is not fully inflected by categories that are marked inflectionally in language,such as tense,aspect,mood,number,gender,and person.As a result,a non-finite verb cannot generally serve as the main verb in an independent clause; rather,it heads a non-finite clause.
By some accounts,a non-finite verb acts simultaneously as a verb and as another part of speech; it can take adverbs and certain kinds of verb arguments,producing a verbal phrase (i.e.,non-finite clause),and this phrase then plays a different role — usually noun,adjective,or adverb — in a greater clause.This is the reason for the term verbal; non-finite verbs have traditionally been classified as verbal nouns,verbal adjectives,or verbal adverbs.
English has three kinds of verbals:participles,which function as adjectives; gerunds,which function as nouns; and infinitives,which have noun-like,adjective-like,and adverb-like functions.Each of these kinds of verbals is also used in various common constructs; for example,the past participle is used in forming the perfect aspect (to have done).