Editing Auxiliary verb (section)

===List of auxiliaries in English===
A list of verbs that (can) function as auxiliaries in English is as follows:<ref>For lists of the auxiliary verbs like the one produced here but with minor discrepancies, see for instance Radford (2004:324), Crystal (1997:35), and Jurafsky and Martin (2000:322).</ref>

::''be'', ''can'', ''could'', ''dare'', ''do'', ''have'', ''may'', ''might'', ''must'', ''need'', ''ought'', ''shall'', ''should'', ''will'', ''would''

The status of ''dare (not)'', ''need (not)'', and ''ought (to)'' is debatable<ref>For some discussion of the status of ''dare'' as a "marginal modal", see Fowler's Modern English Usage, p. 195f.</ref> and the use of these verbs as auxiliaries can vary across dialects of English. If the negative forms ''can't'', ''don't'', ''won't'', etc. are viewed as separate verbs (and not as contractions), then the number of auxiliaries increases. The verbs ''do'' and ''have'' can also function as full verbs or as [[light verb]]s, which can be a source of confusion about their status. The [[English modal verb|modal verb]]s (''can'', ''could'', ''may'', ''might'', ''must'', ''shall'', ''should'', ''will'', ''would'', and ''dare'', ''need'' and ''ought'' when included) form a subclass of auxiliary verbs. Modal verbs are [[Defective verb|defective]] insofar as they cannot be [[inflection|inflected]], 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.

{| class="wikitable"
|-
! Auxiliary verb !! Meaning contribution !! Example
|-
| be<sub>1</sub> || [[Copula (linguistics)|copula]] (= [[linking verb]]) || She '''is''' the boss. 
|-
| be<sub>2</sub> || [[progressive aspect]] || He '''is''' sleeping.
|-
| be<sub>3</sub> || [[passive voice]] || They '''were''' seen.
|-
| can<sub>1</sub> || [[deontic modality]] || I '''can''' swim. 
|-
| can<sub>2</sub> || [[epistemic modality]] || Such things '''can''' help.
|-
| could<sub>1</sub> || deontic modality || I '''could''' swim.
|-
| could<sub>2</sub> || epistemic modality || That '''could''' help. 
|-
| dare || deontic modality || I '''dare''' not attempt it.
|-
| do<sub>1</sub> || [[do-support]]/emphasis || You '''did''' not understand.
|-
|do<sub>2</sub>
|question
|'''Do''' you like it?
|-
| have || [[perfect aspect]] || They '''have''' understood.
|-
| may<sub>1</sub> || deontic modality || '''May''' I stay?
|-
| may<sub>2</sub> || epistemic modality || That '''may''' take place.
|-
| might || epistemic modality || We '''might''' give it a try.
|-
| must<sub>1</sub> || deontic modality || You '''must''' not mock me.
|-
| must<sub>2</sub> || epistemic modality || It '''must''' have rained.
|-
| need || deontic modality || You '''need''' not water the grass.
|-
| ought || deontic modality || You '''ought''' to play well.
|-
| shall || deontic modality || You '''shall''' not pass.
|-
| should<sub>1</sub> || deontic modality || You '''should''' listen.
|-
| should<sub>2</sub> || epistemic modality || That '''should''' help. 
|-
| will<sub>1</sub> || epistemic modality || We '''will''' eat pie.
|-
| will<sub>2</sub> || [[future tense]] || The sun '''will''' rise tomorrow at 6:03.
|-
| will<sub>3</sub> || [[habitual aspect]] || He '''will''' make that mistake every time.
|- 
| would<sub>1</sub> || epistemic modality || Nothing '''would''' accomplish that.
|-
| would<sub>2</sub> || [[future-in-the-past]] tense || After 1990, we '''would''' do that again.
|-
| would<sub>3</sub> || habitual aspect || Back then we '''would''' always go there.
|}

Deontic [[Modality (grammar)|modality]] 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.