Nonfinite verb

A nonfinite verb is any of several verb forms that are not finite verbs; they cannot serve as the root of an independent clause. Most nonfinite verbs found in English are infinitives, participles and gerunds. (They sometimes are called verbals, but that term has traditionally applied only to participles and gerunds.) Additional nonfinite forms found in some other languages include converbs, gerundives and supines.

Nonfinite verbs typically are not inflected by grammatical tense, and they have little inflection for other grammatical categories. Generally, they also lack a subject dependent. One or more nonfinite verbs may be associated with a finite verb in a finite clause: the elements of a verb catena, or verb chain.

Because English lacks most inflectional morphology, the finite and the nonfinite forms of a verb may appear the same in a given context. In such a case, the environment surrounding the verb must be examined to determine whether it is finite or nonfinite.

The following sentences each contain one finite verb (underlined) and multiple nonfinite verbs (in bold):

In the above sentences, been, examined and done are past participles, want, have, refuse, accept and get are infinitives, and coming, running and trying are present participles (for alternative terminology, see the sections below).

In languages like English that have little inflectional morphology, certain finite and nonfinite forms of a given verb are often identical, e.g.

Despite the fact that the verbs in bold have the same outward appearance, the first in each pair is finite and the second is nonfinite. To distinguish the finite and nonfinite uses, one has to consider the environments in which they appear. Finite verbs in English usually appear as the leftmost verb in a verb catena. For details of verb inflection in English, see English verbs.

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