English irregular verbs

The English language has many irregular verbs, approaching 200 in normal use – and significantly more if prefixed forms are counted. In most cases, the irregularity concerns the past tense or the past participle. The other inflected parts of the verb – the third person singular present indicative in -s, and the present participle and gerund form in -ing – are formed regularly in most cases. There are a few exceptions: the verb be has irregular forms throughout the present tense; the verbs have, do, and say have irregular -s forms; and certain defective verbs lack most inflection.
Irregular verbs in Modern English include many of the most common verbs: the dozen most frequently used English verbs are all irregular. New verbs usually follow the regular inflection, unless they are compound formations from an existing irregular verb.
Irregular verbs typically followed more regular patterns at a previous stage in the history of English. In particular, many such verbs derive from strong verb">Germanic strong verbs">strong verbs, which make many of their inflected forms through vowel gradation, as can be observed in Modern English patterns such as sing–sang–sung. The regular verbs, on the other hand, with their preterites and past participles ending in -ed, follow the weak verb|weak conjugation], which originally involved adding a dental consonant . Nonetheless, there are also many irregular verbs that follow or partially follow the weak conjugation.
For information on the conjugation of regular verbs in English, as well as other points concerning verb usage, see English verbs.

Development

Most English irregular verbs are native, derived from verbs that existed in Old English. Nearly all verbs that have been borrowed into the language at a later stage have defaulted to the regular conjugation. There are a few exceptions, however, such as the verb catch, whose irregular forms originated by way of analogy with native verbs such as teach.
Most irregular verbs exist as remnants of historical conjugation systems. When some grammatical rule became changed or disused, some verbs kept to the old pattern. For example, before the Great Vowel Shift, the verb keep belonged to a group of verbs whose vowel was shortened in the past tense; this pattern is preserved in the modern past tense kept. Verbs such as peep, which have similar form but arose after the Vowel Shift, take the regular -ed ending.
The force of analogy tends to reduce the number of irregular verbs over time, as irregular verbs switch to regular conjugation patterns. This is more likely to occur with less common verbs ; hence it is often the more common verbs that tend to remain irregular. Many irregular verbs today have coexisting irregular and regular forms.
In a few cases, however, analogy has operated in the other direction. This is the case with the example of catch given above; others include wear and string, which were originally weak verbs, but came to be conjugated like the similar-sounding strong verbs bear and swing.
In American English, the regular forms of verbs account for more than 90% of instances, whereas British English has a regular form frequency of 69% according to a 1991 study.
The verb forms described in this article are chiefly those that are accepted in standard English; many regional dialects have different irregular forms, such as sneak–''snuck and dive-dove, common in the United States, as opposed to standard sneaked and dived'' respectively. In particular, it is fairly common in some types of non-standard speech to use past tenses as past participles, and vice versa; e.g. "have went" instead of "have gone" in Southern American English.

Groups

The irregular verbs of Modern English form several groups with similar conjugation pattern and historical origin. These can be broadly grouped into two classes – the Germanic weak and strong groups – although historically some verbs have moved between these groups. There are also a few anomalous cases: the verbs be and go, which demonstrate suppletion; the verb do; and the defective modal verbs.

Strong verbs

Many irregular verbs derive from Germanic strong verbs, which display the vowel shift called ablaut, and do not add an ending such as -ed or -t for the past forms. These sometimes retain past participles with the ending -n, as in give–gave–given and ride–rode–ridden, but in other cases this ending has been dropped, as in come–came–come and sing–sang–sung. This verb group was inherited from the parent Proto-Germanic language, and before that from the Proto-Indo-European language. It was originally a system of regular verbs, and in Old English and modern German the system remains more or less regular; however in Modern English relatively few verbs continue to follow such a pattern, and they are classed as irregular.
Verbs that retain a strong-type inflection in modern English and add -n in the past participle include bear, beat, beget, bite, blow, break, choose, cleave, draw, drive, eat, fall, fly, forbid, forget, forsake, freeze, get, give, grow, know, lie, ride, rise, see, shake, shear, slay, smite, speak, steal, stride, strive, swear, take, tear, throw, tread, wake, weave, and write.
Those that do not add -n in the usual past participle include become, begin, bind, burst, cling, come, drink, fight, find, fling, grind, hang, hold, let, ring, run, seek, shed, shine, shit, shoot, shrink, sing, sink, sit, slide, sling, slink, slit, spin, spring, stand, sting, stink, strike, swim, swing, win, wind and wring.
The verbs sow and swell are now usually regular in the past tense, but retain the strong-type past participles sown and swollen. Other verbs retain participles in -n for certain adjectival uses and distinguish them from other usage in perfect tenses. The participle in -n may sometimes be limited to certain specific usage, as in molten used only to refer to metals. Sometimes the connection between the infinitive and the adjective is not perceived as obvious any more, e.g. seethe – sodden. The verb crow is now regular in the past participle, but the strong past tense crew is sometimes used.
Some originally weak verbs have taken on strong-type forms by analogy with strong verbs. These include dig, dive, hide, prove, saw, sew, show, spit, stick, strew, string, and wear.
For indication of the groups of strong verbs the listed words belong to, see the table at List of English irregular verbs.

Weak verbs

Some other irregular verbs derive from Germanic weak verbs, forming past tenses and participles with a -d or -t ending. The weak conjugation is also the origin of the regular verbs ending in -ed; however various historical sound changes have led to certain types of irregularity in some verbs. The main processes are as follows.

Some weak verbs with long vowels in their present tense stems took a short vowel in the past tense and past participle.
In some weak verbs ending in a final -t or -d, this final consonant coalesced with the weak past ending to leave a single -t or -d in the past forms.
Some verbs ending in l or n had their past ending irregularly devoiced to -t, and in a few verbs ending with a v or z sound, both that sound and the past ending were devoiced.
Some weak verbs continue the vowel shift called Rückumlaut. Details of the history of these verbs can be found under Germanic weak verb; those with -gh- in the spelling were also affected by the Germanic spirant law.
A few weak verbs have undergone additional contractions or vowel shortenings in their past or present tense forms.
A few verbs are regular in their spoken forms, but have irregular spelling.

The irregular weak verbs can consequently be grouped as follows:

Verbs with vowel shortening: creep, flee, hear, keep, leap, shoe, sleep, sweep and weep.
Verbs with vowel shortening and devoicing of the ending: deal, dream, feel, kneel, lean, leave, lose and mean. Some of the verbs in this and in the preceding group have alternative regular forms, such as dreamed and leaped.
Verbs with coalescence of consonants: bet, bid, cast, cost, cut, fit, hit, hurt, knit, put, quit, rid, set, shed, shut, split, spread, thrust, wed and wet. Some of these verbs have alternative regular forms, such as wedded and wetted.
Verbs with coalescence of consonants and devoicing of the ending: bend, build, lend, rend, send, spend.
Verbs with coalescence of consonants and vowel shortening: bleed, breed, feed, lead, light, meet, read, and speed.
Verbs with devoicing of the ending and no other irregularity: burn, dwell, learn, smell, spell, spill and spoil. Most of these have regular -ed forms as alternatives.
Verbs continuing the Rückumlaut pattern: bring–brought, buy–bought, seek–sought, sell–sold, teach–taught, tell–told, and think–thought. The borrowed verb catch has also fallen into this pattern as a result of analogy.
Verbs with additional contractions and shortenings: have–has–had, make–made, say–says–said.
Verbs irregular only in spelling: lay–laid, pay–paid.

For weak verbs that have adopted strong-type past tense or past participle forms, see the section above on strong verbs. More information on the development of some of the listed verbs can be found at List of irregular verbs.

Anomalous cases

The following verbs do not fit exactly into any of the above categories:

The modal verbs, which are defective verbs – they have only a present indicative form and a preterite, lacking nonfinite forms, imperatives, and subjunctives. Moreover, they do not add -s in the third person singular – this is because they derive either from preterites, or from Germanic preterite-present verbs, which were conjugated using the preterite form with present tense meaning. The chief verbs of this closed class are can–could, may–might, shall–should, will–would, and must and ought. There are also dare and need, which follow the same pattern in some contexts: "Dare he jump? She needn't worry". In some cases, used to is also listed as a modal verb. All the modal verbs both in their present and preterite forms-except for dare, need and used to-usually refer to the present or the future, not the past. To express the past, modal verbs typically use suppletive forms. The only two modal verbs that do distinguish the preterite forms are dare and need. See.
Two verbs that contain suppletive forms, i.e. one or more of their parts came from an entirely different root. With go this applies to the past tense went, which is originally from the verb wend. With be it applies to a number of different forms. For details, see Indo-European copula and the article on the verb go. Derived from be is the defective verb beware, which does not inflect in normal use and which appears only in those forms in which the plain form of be would be used, namely the infinitive, the imperative, and the subjunctive.
The verb do, which has the reduplicated form did for its past tense, an irregularity that is shared with other Germanic languages. Its past participle done can be compared to typical strong participles in -n; however both this and the third person present tense does feature a short vowel in modern pronunciation:,.

Verbs with irregular present tenses

Apart from the modal verbs, which are irregular in that they do not take an -s in the third person, the only verbs with irregular present tense forms are be, do, have, say and an archaic verb wit.
The verb be has multiple irregular forms. In the present indicative it has am in the first person singular, is, which is pronounced with a Z sound, in the third person singular, and are, which is pronounced with an sound, in the plural and second person singular. It also has two past tense forms: was, which is pronounced with an sound in US English, for the first and third persons singular, and were, which is pronounced with an sound, for the plural and second person singular. The past participle is been, which is pronounced with an sound in US English, and the present participle and gerund forms are regular: being. For more details see Indo-European copula.
As mentioned above, apart from its other irregularities, the verb do, which is pronounced with an sound, has the third person present indicative does & past participle done pronounced with short vowels: .
The verb have, which is pronounced with an sound, has a contracted third person present indicative form: has . This is formed similarly to the verb's past tense had.
The verb say displays vowel shortening in the third person present indicative : says. The same shortening occurs in the past form said.
The verb wit is the only non-modal verb that is also a preterite-present verb and it does not take -s in the third person. It also has a vowel shift in the present tense as in "I wot".
For shortened forms of certain verbs and of their negations, see English auxiliaries and contractions.

Coincident forms

In regular English verbs, the past tense and past participle have the same form. This is also true of most irregular verbs that follow a variation of the weak conjugation, as can be seen in the list below. Differences between the past tense and past participle generally appear in the case of verbs that continue the strong conjugation, or in a few cases weak verbs that have acquired strong-type forms by analogy – as with show. However, even some strong verbs have identical past tense and participle, as in cling–clung–clung.
In some verbs, the past tense, past participle, or both are identical in form to the basic form of the verb. This is the case with certain strong verbs, where historical sound changes have led to a leveling of the vowel modifications: for example, let has both past tense and past participle identical to the infinitive, while come has the past participle identical. The same is true of the verbs listed above under as having undergone coalescence of final consonants : bet, bid, etc.. The verb read has the same spelling in all three forms, but not the same pronunciation for the past tense and past participle, as it exhibits vowel shortening.
In a few cases the past tense of an irregular verb has the same form as the infinitive of a different verb. For example, bore and found may be past tenses of bear and find, but may also represent independent verbs of different meaning. Another example is lay, which may be the past tense of lie, but is also an independent verb. In fact the past tense verb lay derives from a causative of the verb from which lie derives. The two verbs are sometimes confused, with lay used in the intransitive senses prescriptively reserved for lie.

Prefixed verbs

Nearly all of the basic irregular verbs are single-syllable words. Their irregular inflected forms are generally single-syllable also, except for the past participles in -en like chosen and risen. However, many additional irregular verbs are formed by adding prefixes to the basic ones: understand from stand, become from come, mistake from take, and so on. As a general rule, prefixed verbs are conjugated identically to the corresponding basic verbs; e.g. understand–understood–understood and become–became–become, following the patterns of stand–stood–stood and come–came–come. However, there are occasional differences: in British English, for instance, the past participle of get is got, while that of forget is forgotten.
Only a few irregular verbs of more than one syllable cannot be analyzed as prefixed compounds of monosyllables. There is begin–began–begun. There is also forsake–forsook–forsaken. There is also beseech–besought–besought ; however the form besought is now archaic, the verb normally being conjugated regularly.

List

The following is a list of irregular verbs that are commonly used in standard modern English. It omits many rare, dialectal, and archaic forms, as well as most verbs formed by adding prefixes to basic verbs. It also omits past participle forms that remain in use only adjectivally. For a more complete [|list], with derivations, see List of English irregular verbs. Further information, including pronunciation, can be found . The list that follows shows the base, or infinitive form, the past tense and the past participle of the verb.

a- : for abide, arise, awake, see bide, rise, wake
be – was, were – been
be- : for become, befall, beset, etc. see come, fall, set, etc.
bear – bore – borne
beat – beat – beaten
beget – begot – begot
begin – began – begun
bend – bent – bent
bet – bet – bet
beware – defective verb
bid – bid – bid
bid – bade/bid – bidden/bid
bide – bided/bode – bided/bidden
bind – bound – bound
bite – bit – bitten
bleed – bled – bled
blow – blew – blown
break – broke – broken
breed – bred – bred
bring – brought – brought
build – built – built
burn – burnt/burned – burnt/burned
burst – burst – burst
buy – bought – bought
can – could
cast – cast – cast
catch – caught – caught
choose – chose – chosen
clad – clad/cladded – clad/cladded
cleave – clove/cleft – cloven/cleft
cling – clung – clung
come – came – come
cost – cost/costed – cost/costed
creep – crept/creeped – crept/creeped
crow – crowed/crew – crowed
cut – cut – cut
dare – regular except for possible third person singular present dare
deal – dealt – dealt
dig – dug – dug
dive – dived/dove – dived
do – did – done
drag – dragged/drug – dragged/drug
draw – drew – drawn
dream – dreamed/dreamt – dreamed/dreamt
drink – drank – drunk
drive – drove – driven
dwell – dwelt/dwelled – dwelt/dwelled
eat – ate – eaten
fall – fell – fallen
feed – fed – fed
feel – felt – felt
fight – fought – fought
find – found – found
fit – fit/fitted – fit/fitted
flee – fled – fled
fling – flung – flung
fly – flew – flown
for- : for forgo, foresee, etc. see go, see, etc.
forbid – forbade/forbid – forbidden
forget – forgot – forgotten
forsake – forsook – forsaken
freeze – froze – frozen
get – got – gotten/got
gild – gilded/gilt – gilded/gilt
give – gave – given
go – went – gone
grind – ground – ground
grow – grew – grown
hang – hung/hanged – hung/hanged
have – had – had
hear – heard – heard
hew – hewed – hewn/hewed
hide – hid – hidden
hit – hit – hit
hoist – hoist/hoisted – hoist/hoisted
hold – held – held
hurt – hurt – hurt
in- : for inlay, input, etc. see lay, put, etc.
inter- : for interlay, interweave, etc. see lay, weave, etc.
keep – kept – kept
kneel – knelt/kneeled – knelt/kneeled
knit – knit/knitted – knit/knitted
know – knew – known
lay – laid – laid
lead – led – led
lean – leaned/leant – leaned/leant
leap – leaped/leapt – leaped/leapt
learn – learned/learnt – learned/learnt
leave – left – left
lend – lent – lent
let – let – let
lie – lay – lain
light – lit/lighted – lit/lighted
lose – lost – lost
make – made – made
may – might
mean – meant – meant
meet – met – met
mis- : for misspeak, mistake, etc. see speak, take, etc.
mow – mowed – mowed/mown
must – defective
need – regular except for possible third person singular present need
off- : for offset see set, etc.
ought – defective
out- : for outbid, output, etc. see bid, put, etc.
over- : for overbid, overdo, etc. see bid, do, etc.
pay – paid – paid
plead – pleaded/pled – pleaded/pled
pre- : for prepay, preset, etc. see pay, set, etc.
prove – proved – proved/proven
put – put – put
quit – quitted/quit – quitted/quit
re- : for redo, remake, etc. see do, make, etc.
read – read – read
rend – rent – rent
rid – rid/ridded – rid/ridded/ridden
ride – rid/rode – ridden
ring – rang – rung
rise – rose – risen
run – ran – run
saw – sawed – sawn/sawed
say – said – said
see – saw – seen
seek – sought – sought
sell – sold – sold
send – sent – sent
set – set – set
sew – sewed – sewn/sewed
shake – shook – shaken/shook
shall – should
shear – sheared/shore – shorn/sheared
shed – shed – shed
shine – shone/shined – shone/shined
shit – shat/shit/shitted – shat/shit/shitted
shoe – shoed/shod – shoed/shod
shoot – shot – shot
show – showed – shown/showed
shrink – shrank/shrunk – shrunk
shrive – shrove – shriven
shut – shut – shut
sing – sang – sung
sink – sank – sunk
sit – sat – sat
slay – slew/slayed – slain/slayed
sleep – slept – slept
slide – slid – slid
sling – slung – slung
slink – slunk – slunk
slit – slit – slit
smell – smelled/smelt – smelled/smelt
smite – smote – smitten
sneak – sneaked/snuck – sneaked/snuck
sow – sowed – sown/sowed
speak – spoke – spoken
speed – sped/speeded – sped/speeded
spell – spelled/spelt – spelled/spelt
spend – spent – spent
spill – spilled/spilt – spilled/spilt
spin – span/spun – spun
spit – spat/spit – spat/spit
split – split – split
spoil – spoiled/spoilt – spoiled/spoilt
spread – spread – spread
spring – sprang/sprung – sprung
stand – stood – stood
stave – staved/stove – staved/stove
steal – stole – stolen
stick – stuck – stuck
sting – stung – stung
stink – stank – stunk
strew – strewed – strewn/strewed
stride – strode – stridden/strode
strike – struck – struck/stricken
string – strung – strung
strive – strove/strived – striven/strived
swear – swore – sworn
sweat – sweated/sweat – sweated/sweat
sweep – swept – swept
swell – swelled – swollen/swelled
swim – swam – swum
swing – swang/swung – swung
take – took – taken
teach – taught – taught
tear – tore – torn
tell – told – told
text – texted/text – texted/text
think – thought – thought
thrive – thrived/throve – thrived/thriven
throw – threw – thrown
thrust – thrust/thrusted – thrust/thrusted
tread – trod – trodden/trod
un- : for unbend, unweave, etc. see bend, weave, etc.
under- : for underlie, undergo, understand, etc. see lie, go, stand, etc.
up- : for upset see set, etc.
wake – woke – woken
wear – wore – worn
weave – wove – woven
wed – wed/wedded – wed/wedded
weep – wept – wept
wet – wet/wetted – wet/wetted
will – would
win – won – won
wind – wound – wound
with- : for withdraw, withhold, withstand, see draw, hold, stand
wring – wrang/wrung – wrung
write – wrote – ''written''

In language acquisition

Steven Pinker's book Words and Rules describes how mistakes made by children in learning irregular verbs throw light on the mental processes involved in language acquisition. The fact that young children often attempt to conjugate irregular verbs according to regular patterns indicates that their processing of the language involves the application of rules to produce new forms, in addition to the simple reproduction of forms that they have already heard.
See also.