 | The examples and perspective in this articlemay not represent aworldwide view of the subject. You mayimprove this article, discuss the issue on thetalk page, orcreate a new article, as appropriate.(January 2016) (Learn how and when to remove this message) |
Anauxiliary verb (abbreviatedaux) is averb that adds functional or grammatical meaning to theclause in which it occurs, so as to expresstense,aspect,modality,voice, emphasis, etc. Auxiliary verbs usually accompany aninfinitive verb or aparticiple, which respectively provide the main semantic content of the clause.[1] An example is the verbhave in the sentenceI have finished my lunch. Here, the auxiliaryhave helps to express theperfect aspect along with the participle,finished. Some sentences contain a chain of two or more auxiliary verbs. Auxiliary verbs are also calledhelping verbs,helper verbs, or(verbal) auxiliaries. Research has been conducted into split inflection in auxiliary verbs.[2]
Below are some sentences that contain representative auxiliary verbs fromEnglish,Spanish,German andFrench, with the auxiliary verb marked in bold:
These auxiliaries help express a question, show tense/aspect, or form passive voice. Auxiliaries like these typically appear with a full verb that carries the main semantic content of the clause.
Auxiliary verbs typically help express grammaticaltense,aspect,mood, andvoice. They generally appear together with an infinitive. The auxiliary is said to "help" the infinitive. The auxiliary verbs of a language form aclosed class, i.e., there is a fixed, relatively small number of them.[8]
Widely acknowledged verbs that can serve as auxiliaries in English and many related[clarification needed] languages are the equivalents ofbe to express passive voice, andhave (and sometimesbe) to expressperfect aspect or past time reference.[9]
In some treatments, thecopulabe is classed as an auxiliary even though it does not "help" another verb, e.g.,
Definitions of auxiliary verbs are not always consistent across languages, or even among authors discussing the same language.Modal verbs may or may not be classified as auxiliaries, depending on the language. In the case of English, verbs are often identified as auxiliaries based on their grammatical behavior, as described below. In some cases, verbs that function similarly to auxiliaries, but are not considered full members of that class (perhaps because they carry some independent lexical information), are calledsemi-auxiliaries. In French, for example, verbs such asdevoir (have to),pouvoir (be able to),aller (begoing to),vouloir (want),faire (make), andlaisser (let), when used together with the infinitive of another verb, can be called semi-auxiliaries.[10] There has also been a study on auxiliary verb constructions in Dravidian languages.[11][relevant?]
The following sections consider auxiliary verbs in English. They list auxiliary verbs, then present the diagnostics that motivate this special class (subject-auxiliary inversion and negation withnot). Themodal verbs are included in this class, due to their behavior with respect to these diagnostics.
A list of verbs that (can) function as auxiliaries in English is as follows:[12]be,can,could,dare,do,have,may,might,mote,must,need,ought,shall,should,will,would
The status ofdare (not),need (not), andought (to) is debatable[13] and the use of these verbs as auxiliaries can vary across dialects of English. If the negative formscan't,don't,won't, etc. are viewed as separate verbs (and not as contractions), then the number of auxiliaries increases. The verbsdo andhave can also function as full verbs or aslight verbs, which can be a source of confusion about their status. Themodal verbs (can,could,may,might,must,shall,should,will,would, anddare,need andought when included) form a subclass of auxiliary verbs. Modal verbs aredefective insofar as they cannot beinflected, nor do they appear as gerunds, infinitives, or participles.
The following table summarizes the auxiliary verbs in standard English and the meaning contribution to the clauses in which they appear. Many auxiliary verbs are listed more than once in the table based upon discernible differences in use.
| Auxiliary verb | Meaning contribution | Example |
|---|---|---|
| be1 | copula (=linking verb) | Sheis the boss. |
| be2 | progressive aspect | Heis sleeping. |
| be3 | passive voice | Theywere seen. |
| can1 | ability | Ican swim. |
| can2 | permission (deontic modality) | Can I come in? |
| can3 | suggestion or offer (deontic modality) | Ican come with you. |
| could1 | past tense of can1 | Icould swim (back then). |
| could2 | past tense of can2 | Icouldn't leave. |
| could3 | can1hypothetical | Icouldn't play guitar without hands. |
| could4 | can2hypothetical | Icould participate if I was over 18. |
| could5 | can3hypothetical | Icould stay here in case he comes back. |
| could6 | can1 uncertain | Thatcould help. |
| could7 | can2 uncertain or hesitant | Could I come in? |
| could8 | can3 uncertain or hesitant | Icould say something if you want me to. |
| dare | deontic modality | Idare not attempt it. |
| do1 | do-support for negation | Youdid not understand. |
| do2 | emphatic do | Ido understand. |
| do3 | question-formingdo-support | Do you understand? |
| have | perfect aspect | Theyhave understood. |
| may1 | permission (deontic modality) | May I stay? |
| may2 | possibility (epistemic modality) | Thatmay happen. |
| might1 | possibility (epistemic modality) | Thatmight happen. |
| might2 | humble request (deontic modality) | Might I ask for your advice? |
| mote | optative mood | Somote it be. |
| must1 | obligation (deontic modality) | Youmust not mock me. |
| must2 | logical deduction (epistemic modality) | Itmust have rained. |
| need | deontic modality | Youneed not water the grass. |
| ought1 | exhortation orjudgment (deontic modality) | Youought to stay home after dark. |
| ought2 | expectation (epistemic modality) | Youought to play well after a good night's sleep. |
| shall1 | insistence or obligation (deontic modality) | The rentershall be responsible for the damage. |
| shall2 | permission (deontic modality) | Youshall enter. |
| should1 | advice (deontic modality) | Youshould listen. |
| should2 | expectation (epistemic modality) | Thatshould help. |
| should3 | hypothetical (epistemic modality) | If Ishould fail, please help me. |
| should have | past tense of shall | The landlordshould have paid for it. |
| will1 | future tense | The sunwill rise tomorrow at 6:03. |
| will2 | habitual aspect | Hewill make that mistake every time. |
| will3 | predictive inference (epistemic modality) | Hewill be home by now. |
| will4 | ability | Only one keywill fit. |
| will5 | intention or request (deontic modality) | Iwill have a Caesar salad. |
| would1 | past tense of will1 (future-in-the-past) | After 1990, wewould do that again. |
| would2 | past tense of will2 | Back then wewould always go there. |
| would3 | past tense of will3 | Hewould be home. |
| would4 | past tense of will4 | Only one keywould fit. |
| would5 | past tense of will5 | Wewould have pie. |
| would6 | hypothetical of will1 | Iwould go tomorrow. |
| would7 | hypothetical of will2 | Hewould make that mistake every time. |
| would8 | hypothetical of will3 | Hewould be home by now. |
| would9 | hypothetical of will4 | The shirtwould fit if I lost weight. |
| would have | past tensehypothetical of will | Hewould have gone home. |
Deonticmodality expresses an ability, necessity, or obligation that is associated with an agent subject. Epistemic modality expresses the speaker's assessment of reality or likelihood of reality. Distinguishing between the two types of modality can be difficult, since many sentences contain a modal verb that allows both interpretations.
African American Vernacular English makes a variety of finertense/aspect distinctions than other dialects of English by making use of unique variant forms of, in particular:habitual 'be', reduced 'done' (dən), and stressed 'been' (BIN):[14][15]
| Auxiliary | Meaning | Example |
|---|---|---|
| be | habitual aspect | Shebe telling people she eight. 'She is always telling people she's eight' |
| done | resultative modality | Idone pushed it. 'I have (already) pushed it' |
| been | distant past tense | Ibeen knew that. 'I've known that for a long time' |
The verbs listed in the previous section can be classified as auxiliaries based upon two diagnostics: they allowsubject–auxiliary inversion (the type of inversion used to form questions etc.) and (equivalently) they can takenot as a postdependent (a dependent that follows itshead). The following examples illustrate the extent to which subject–auxiliary inversion can occur with an auxiliary verb but not with a full verb.[16] (The asterisk * is the means commonly used in linguistics to indicate that the example is grammatically unacceptable or that a particular construction has never been attested in use).
The following examples illustrate that the negationnot can appear as a postdependent of a finite auxiliary verb, but not as a postdependent of a finite full verb:[17]
A third diagnostic that can be used for identifying auxiliary verbs is verb phrase ellipsis. See the article onverb phrase ellipsis for examples.
These criteria lead to thecopulabe and non-copular use ofbe as anexistential verb being considered an auxiliary (it undergoes inversion and takes postdependentnot, e.g.,Is she the boss?,She is not the boss,Is there a God?,There is a God). However, if one definesauxiliary verb as a verb that somehow "helps" another verb, then the copulabe is not an auxiliary, because it appears without another verb. The literature on auxiliary verbs is somewhat inconsistent in this area.[18]
There are also some properties that some but not all auxiliary verbs have. Their presence can be used to conclude that the verb is an auxiliary, but their absence does not guarantee the converse. One such property is to have the same form in the present tense, also for the first and the third person singular. This in particular is typical formodal auxiliary verbs, such aswill andmust. (Examples:He will come tomorrow,she must do it at once, nothe wills orshe musts.)
Some syntacticians distinguish between auxiliary verbs andlight verbs.[19][20] The two are similar insofar as both verb types contribute mainly just functional information to the clauses in which they appear. Hence both do not qualify as separatepredicates, but rather they form part of a predicate with another expression – usually with a full verb in the case of auxiliary verbs and usually with a noun in the case of light verbs.
In English, light verbs differ from auxiliary verbs in that they cannot undergo inversion and they cannot takenot as a postdependent. The verbshave anddo can function as auxiliary verbs or as light verbs (or as full verbs). When they are light verbs, they fail the inversion and negation diagnostics for auxiliaries, e.g.
Note that in some dialects (for example, the West and South West dialects ofHiberno-English), the inversion test may sound correct to native speakers.
(In some cases, though,have may undergo auxiliary-type inversion and negation even when it is not used as an auxiliary verb – seeSubject–auxiliary inversion § Inversion with other types of verb.)
Sometimes the distinction between auxiliary verbs and light verbs is overlooked or confused. Certain verbs (e.g.,used to,have to, etc.) may be judged as light verbs by some authors, but as auxiliaries by others.[21]
{{cite book}}: CS1 maint: multiple names: authors list (link) CS1 maint: numeric names: authors list (link)