Nonfinite verb - AshokBhat/grammar GitHub Wiki
A '''nonfinite verb''' is a verb that is not Finite verb. Nonfinite verbs cannot perform action as the root of an independent clause.
Most nonfinite verbs found in English language are infinitives, participles and gerunds.
Nonfinite verbs typically are not inflection by grammatical tense, and they have little inflection for other grammatical category.
Generally, they also lack a subject (grammar) dependent. One or more nonfinite verbs may be associated with a finite verb in a finite clause: the elements of a verb catena (linguistics), 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.
==Examples== The following sentences each contain one finite verb (underlined) and multiple '''nonfinite''' verbs (in bold):
::The proposal has '''been''' intensively '''examined''' today. ::What did they '''want''' to '''have''' '''done''' about that? ::Someone tried to '''refuse''' to '''accept''' the offer. ::'''Coming''' downstairs, she saw the man '''running''' away. ::I am '''trying''' to '''get''' the tickets. 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.
::a. They '''laugh''' a lot. - Finite verb (present tense) in bold ::b. They will '''laugh''' a lot. - Nonfinite infinitive in bold
::a. Tom '''tried''' to help. - Finite verb (past tense) in bold ::b. Tom has '''tried''' to help. - Nonfinite participle in bold
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 (linguistics).Concerning the fact that the left-most verb is the finite verb, see Tallerman (1998:65). For details of verb inflection in English, see English verbs.
==Categories==
===English===
English has three kinds of nonfinite verbs:
::# infinitives,
::# participles, and
::# gerunds
Each of the nonfinite forms appears in a variety of environments.
====Infinitives==== {{main|Infinitive}} The infinitive of a verb is considered the "base" form, listed in dictionaries. English infinitives appear in verb catenae if they are introduced by an auxiliary verb or by a certain limited class of main verbs. They are also often introduced by a main verb followed by the particle ''to'' (as illustrated in the examples below). Further, infinitives introduced by ''to'' can function as noun phrases or even as modifiers of nouns. The following table illustrates such environments:
:::{| class="wikitable"
|-
! Infinitive !! Introduced by a (modal) auxiliary verb !! Introduced by a main verb !! Introduced by a main verb plus ''to'' !! Functioning as noun phrase !! Functioning as the modifier of a noun
|-
| laugh || Do not '''laugh'''! || That made me '''laugh'''. || I tried not to '''laugh'''. || '''To laugh''' would have been unwise. || the reason '''to laugh'''
|-
| leave || They may '''leave'''. || We let them '''leave'''. || They refused to '''leave'''. || '''To leave''' was not an option. || the thing '''to leave''' behind
|-
| expand || You should '''expand''' the explanation. || We had them '''expand''' the explanation. || We hope to '''expand''' the explanation. || '''To expand''' the explanation would have been folly. || the effort '''to expand'''
|}
====Participles==== {{main|Participle}}
English participles can be divided along two lines: according to grammatical aspect (progressive vs. perfect/perfective) and grammatical voice (active vs. passive). The following table illustrates the distinctions:
:::{| class="wikitable"
|-
! Participle !! Progressive active participle !! Perfect active participle !! Passive participle
|-
| fix || The guy is '''fixing''' my bike. || He has '''fixed''' my bike || My bike was '''fixed'''.
|-
| open || I saw the flower '''opening''' up || The flower has '''opened''' up. || The flower has been '''opened''' up.
|-
| support || She watched the news '''supporting''' the point || The news has '''supported''' the point. || I understood the point '''supported''' by the news
|-
| drive || She is '''driving''' our car. || She has '''driven''' our car. || Our car should be '''driven''' often.
|}
Participles appear in a variety of environments. They can appear in periphrastic verb catenae, when they help form the main predicate of a clause, as is illustrated with the trees below. Also, they can appear essentially as an adjective modifying a noun. The form of a given perfect or passive participle is strongly influenced by the status of the verb at hand. The perfect and the passive participles of Germanic strong verbs in Germanic languages are irregular (e.g. ''driven'') and must be learned for each verb. The perfect and passive participles of Germanic weak verbs, in contrast, are regular and are formed with the suffix ''-ed'' (e.g. ''fixed'', ''supported'', ''opened'').
====Gerunds==== {{main|Gerund}}
A gerund is a verb form that appears in positions that are usually reserved for nouns. In English, a gerund has the same form as a progressive active participle and so ends in ''-ing''. Gerunds typically appear as subject or object noun phrases or even as the object of a preposition:
:::{| class="wikitable"
|-
! Gerund !! Gerund as subject !! Gerund as object !! Gerund as object of a preposition
|-
| solve || '''Solving''' problems is satisfying. || I like '''solving''' problems. || No one is better at '''solving''' problems.
|-
| jog || '''Jogging''' is boring. || He has started '''jogging'''. || Before '''jogging''', she stretches.
|-
| eat || '''Eating''' too much made me sick. || She avoids '''eating''' too much. || That prevents you from '''eating''' too much.
|-
| investigate || '''Investigating''' the facts won't hurt.|| We tried '''investigating''' the facts. || After '''investigating''' the facts, we made a decision.
|}
Often, distinguishing between a gerund and a progressive active participle is not easy in English, and there is no clear boundary between the two nonfinite verb forms.
==Theories of syntax== For an overview of dependency grammar structure in modern linguistics analysis, three example sentences are shown. The first sentence, ''The proposal has been intensively examined'', is described as follows.
::File:Non-finite tree 1+'.png
The three verbs together form a chain, or verb catena (in purple), which functions as the predicate of the sentence. The finite verb ''has'' is inflected for person and number, tense, and mood: third person singular, present tense, indicative. The nonfinite verbs ''been'' and ''examined'' are, except for tense, neutral across such categories and are not inflected otherwise. The subject, ''proposal'', is a dependent of the finite verb ''has'', which is the root (highest word) in the verb catena. The nonfinite verbs lack a subject dependent.
The second sentence shows the following dependency structure:
The verb catena (in purple) contains four verbs (three of which are nonfinite) and the particle ''to'', which introduces the infinitive ''have''. Again, the one finite verb, ''did'', is the root of the entire verb catena and the subject, ''they'', is a dependent of the finite verb.
The third sentence has the following dependency structure:
Here the verb catena contains three main verbs so there are three separate predicates in the verb catena.
The three examples show distinctions between finite and nonfinite verbs and the roles of these distinctions in sentence structure. For example, nonfinite verbs can be auxiliary verbs or main verbs and they appear as infinitives, participles, gerunds etc.