Strong verbs

Strong verbs are verbs that form their past tense and past participle forms through a change in vowel; this change is called ablaut. The past participle also ends or formerly ended with the suffix -en.

All disused forms or forms rebuilt on the basis of regular sound changes are in bold. If verbs have regular forms as well, the regular forms will not be listed, since this is mainly about the irregular forms.

A few notes in regard to categorization:
 * The system herein is mainly historical; even if a strong verb's forms were influenced to some extent by those of another class of strong verbs, or the strong verb has become weak, the strong verb will still be listed in its original class. The new forms will be listed alongside it.
 * If an originally strong verb has irregular weak forms, it and the irregular weak forms are listed.
 * Regular verbs that have been made strong by analogy in New English are not included if these forms are not used in standard speech.
 * Derivatives such as understand and arise are not included.
 * A (*) put after a form shows that it is what the strong form would have likeliest become and is not attested in New English.

In each class, the principal parts (that is, the vowel pattern that the verb had in Old English) are given:


 * Infinitive - the vowel in the infinitive.
 * Past singular - the vowel in the first- and third-person singular past indicative.
 * Past plural - the vowel in all persons plural past indicative.
 * Past participle - the vowel in the past participle.

For a list of other irregular verbs, see here. For a list of reconstructed strong verbs, see here.

Class 1
The principal parts of the verb rīdan were:


 * Infinitive: ī - rīdan.
 * Past singular: ā - rād.
 * Past plural: i - ridon.
 * Past participle: i - riden.

The first became ride; the second rode; and the last two rid and ridden, respectively. As one can see, we have two ways of forming the past tense:


 * From the past singular, e.g., drove, shone.
 * From the past plural and the past participle, e.g., bit, slid.

This twofold way of forming the past tense explains that the surviving forms are not fully consistent. For example, the past tense forms for ride were once rode and rid, and rode was chosen over rid. However, in the case of bite, bit was chosen over bote, and in that of slide, slid was chosen over slode; undoubtedly, analogy with irregular weak verbs like light and meet helped establish this. It is reasonable to treat slide as an irregular weak verb now, but since bite still has bitten as its past participle, bite ought to still be treated as a strong verb.

Most of this class's verbs that have stayed strong use the original past participle forms. It can be seen that the past participle forms have a shortened form of the original infinitive vowel, e.g., rīdan (ride), riden (ridden).

This class has been preserved well; all the members that still have this class's strong forms are uniform in the infinitive vowel.

Notes:


 * The pronunciation of shone appears to differ in British English, in which it rhymes with gone instead. The American pronunciation, which has it rhyme with bone, follows this class's pattern.
 * The verb shit is unattested in Old English, but it is attested in the form of besciten, the past participle of the unattested verb bescītan. In Middle English, the verb is found with strong forms. The infinitive vowel was originally long (and shite is still used in a few dialects), but likeliest from influence of the noun and the past participle shitten, the vowel was later shortened. Since shote and shitten are now archaic, for the past tense and the past participle, shit has:
 * Shit - from the past plural and the past participle.
 * Shat - by analogy with the Class 5 verb sit.
 * Shitted - the regularized form.
 * As for why the past tense of strike shifted from stroke to struck, according to Hereward Thimbleby Price, it seems that it was influenced by stuck, since struck became widespread only around the same time that stuck popped up, and it explains why strike is the only Class 1 verb to have such a strong form.
 * The disused past tense form strick, which uses the vowel in the past participle, is seldom attested in the early 17th century; it was likely formed by analogy with verbs like bite and slide.

Notes:


 * Abide (etymologically a derivative of bide) occasionally uses abode as the past tense and even the past participle (the original past participle would be abidden), but it is now generally conjugated regularly.
 * The current verb spew once had the same vowel as other members of this class, as it was spīwan in Old English.

Class 2
The principal parts of the verbs crēopan and sūcan were:


 * Infinitive: ēo, ū - crēopan, sūcan.
 * Past singular: ēa - crēap, sēac.
 * Past plural: u - crupon, sucon.
 * Past participle: o - cropen, socen.

The past singular later came to have the same vowel as the lengthened past participle, whence came such past tense forms as chose and froze.

This class has more or less fallen apart, as no living Class 2 verb uses ea for the past tense. Instead, most Class 2 verbs that stayed strong ended up with forms indistinguishable from those of Class 4. Moreover, not only have most Class 2 verbs become regular, but sound changes have destroyed the original vowel pattern, and so surviving members of this class no longer show consistency in their infinitive vowels.

Notes:


 * The past tense and past participle forms of choose and freeze were affected by Verner's law; the past plural and the past participle of cēosan (choose) were curon and coren, and those of frēosan were fruron and froren. In Middle English, these changes were gotten rid of, as the strong forms adopted the consonant in the infinitive and the present tense by analogy. Later writers such as Milton used frore (a reduced form of the original past participle, which would have become frorn) as a poetic word for frozen.
 * Choose and the now weak verb shoot represent atypical phonetic changes, as their OE forms cēosan and scēotan would have normally yielded cheese and sheet. It seemed that stress was transferred to the second part of the diphthong, perhaps because of the initial palatal consonant.
 * Cleave is rather strange, since OE clēofan would have normally yielded cleeve. Of course, there is no difference in sound now, but cleave and cleeve were formerly pronounced differently. The form cleave appears to have come from confusion with the unrelated weak verb cleave (adhere).
 * The past tense of fly lacks the same vowel as is in the past participle, which makes it an exception to the usual change in verbs of this class. It seems that because of the past participle flown, a past tense form flew was made by analogy with Class 7-1 verbs.

Notes:


 * The past tense and past participle of bid is bid, but in the phrase bid fair, bade and bidden are often used because it has been confused for the Class 5 verb bid.
 * Forbid is not etymologically connected to the Class 5 verb bid (meaning command), but because of the similarity in form and meaning, forbid was later thought to be as a derivative thereof and thus became conjugated so; the past tense is now forbade, and the past participle forbidden.
 * The old past tense and old past participle were bod and bodden (variants bode and boden, wherein the vowels had not been shortened). The shortened vowel was likely due to the dental consonant (compare with shot, sodden, gotten, and trodden).
 * Flee and fly once shared the same past tense and past participle forms, and the two verbs continued to be confused for each other in Middle English. Only later on were they formally differentiated in this aspect. Flee became an irregular weak verb, whereas fly kept its strength.
 * The past participle of shoot has a short vowel, which is likely due to shortening before dental consonants (compare with gotten). The vowel in the past tense is from influence of the past participle or from shortening, and it was later strengthened by analogy with irregular weak verbs like meet and light. Because it is now indistinguishable from those verbs, it is best that it be deemed an irregular weak verb.
 * Likewise, fleet (which originally meant float) had floten as the past participle in Middle English, and in some dialects, flotten is found with the meaning of skimmed (that is, it is the past participle of fleet meaning skim, and it is likely that fleet meaning skim is the same verb as fleet now meaning pass quickly).
 * Sodden, the archaic past participle of seethe, lives on as an adjective that has diverged from the meaning of seethe, as it now means soaked, saturated instead of boiled.
 * That sodden has a d instead of the expected th is due to alterations brought about by Verner's law. In Middle English, an alternative form was sothen (included here to show a variant in which the alteration had been eliminated). A later form of the past tense was sod, which was formed by analogy with sodden.

Subclass 1
The principal parts of the verb singan were:


 * Infinitive: i - singan.
 * Past singular: a - sang.
 * Past plural: u - sungon.
 * Past participle: u - sungen.

Note that in every verb of this subclass, an m or an n follows the vowel.

In Middle English, for many verbs, the forms began to be mixed up, insofar as the past tense form came to have the same vowel as was in the past plural and the past participle. There was no consistency whether the original past tense form was kept, whence there are two ways of forming the past tense for verbs of this subclass:


 * From the past singular: began, sang, swam.
 * From the past plural and past participle: swung, stung.

In other words, it was once correct to say I swang and I wan, but now one says I swung and I won.

Note that for words ending in nd, phonological changes have beclouded the original pattern. In the Middle English period, the vowel in the infinitive, the past tense, and the past participle were lengthened because the vowel was set before the consonant cluster nd. As for find, the past plural and the past participle later became found; the singular form fand had died out. In other words, the past tense form draws its vowel from the past plural and the past participle.

The past participle forms originally ended in -en, but it has been dropped, which leaves the change in vowel as the lone marker of the past participle. Some of the -en forms have become adjectives, e.g., drunken, shrunken, sunken.

This subclass is rather well preserved, as nearly every surviving verb of this subclass has kept at least a trace of the original vowel pattern.

Notes:


 * Run was rinnan or irnan (because of metathesis) in Old English. The expected development of the original form, rin, is now used only in some dialects, and how the standard form became run is somewhat unclear. One possible cause is that the metathesized form was the usual form in Old English (which was also the case for burn, OE beornan, originally brinnan). The metathesized form was passed down to Middle English, and it is guessed that after the vowel changed, metathesis happened again, which yielded run. That metathesis was undone may have been due to influence from Scandinavian forms as well. Another possible cause is that the past plural and the past participle influenced the infinitive.

Notes:


 * Burn (Old English beornan) is the result of metathesis in prehistoric Old English (the expected OE infinitive is brinnan, which would have become brin), and the only attested Old English example of the original form is found in onbran (set fire to (past)).
 * The past tense and past participle of climb in Old English were clamb and geclumben, and the vowel in the infinitive was short, whence the verb followed this subclass's pattern fully. But sometime later, the vowel was lengthened, and the strong forms clamb and clumb became disused in standard speech (though they stayed in use in some dialects). A strong form clomb later appeared (perhaps by analogy with Class 1 verbs), but in the end, however, climb was regularized.

Subclass 2
This class makes up the rest of Class 3 verbs, as these verbs do not have an m or an n following the vowel. The principal parts of the verb bregdan were:


 * Infinitive: e - bregdan.
 * Past singular: æ - brægd.
 * Past plural: u - brugdon.
 * Past participle: o - brogden.

The past plural and the past participle were kept throughout this subclass, but the infinitive and the past singular were highly inconsistent because of phonological developments such as breaking and diphthongization. For comparison, the principal parts of the verbs ceorfan, gieldan, and helpan were:


 * Infinitive: eo, ie, e - ceorfan, gieldan, helpan.
 * Past singular: ea - cearf, geald, healp.
 * Past plural: u - curfon, guldon, hulpon.
 * Past participle: o - corfen, golden, holpen.

The verbs fēolan, frignan, murnan, spurnan were exceptional in their infinitives, but followed the above patterns for the other principal parts.

In Middle English, there was a tendency for the past tense to adopt the past participle's vowel, but in the end, nearly every verb became regular or gained regular forms, and so in contrast to Class 3's other subclass, this subclass has nearly disappeared.

Notes:


 * The old past participle of fight is preserved in the archaic phrase foughten field (battleground).

Notes:


 * The verb burst (Old English berstan) underwent metathesis in Middle English from Old Norse influence, whence the past tense had brast as a variant. However, the verb was later reverted to its original form, and the vowel in the infinitive was later transferred to the past tense and past participle. The past participle ending was later dropped, which left burst to be used for all three functions.
 * Corven and storven became obsolete as past participles. Carven and starven were later formed by analogy with strong verbs that have the same vowel in the infinitive and the past participle, but these forms were, in the end, displaced by the regular forms.
 * Molten is still used as an adjective.
 * Thresh later had thrash as a phonetic variant, and thrash is now the form generally used to mean beat, flog, though thresh, in addition to having the same meaning as thrash, also has the specialized meaning of separate grain from a plant.

Class 4
The principal parts of the verb teran were:


 * Infinitive: e - teran.
 * Past singular: æ - tær.
 * Past plural: ǣ - tǣron.
 * Past participle: o - toren.

This class had two anomalous verbs in Old English: cuman (come) and niman (the archaic verb nim, meaning take).

Note that in a Class 4 verb, the vowel is followed by a liquid or a nasal. The two exceptions are brecan (break) and hlecan (cohere), both of which apparently had originally been Class 5, but had already gotten a past participle of this class by analogy.

The past tense forms developed into such forms as tare, brake, and bare, but they became influenced by the vowel in the past participle and so were changed into tore, broke, and bore.

Class 4, though small, has been preserved rather well; nearly every normal Class 4 verb is uniform in their past tense and past participle forms.

Notes:


 * Derivatives of bear use borne as the past participle, e.g., forbear - forborne.
 * The past tense of OE cuman was cōm, which would have normally yielded coom. However, the a form began to be used in late Old English and later overthrew the old form in the standard speech. The a form was apparently formed by analogy with Class 4 and 5 verbs, and the vowel was later lengthened, which yielded came.
 * Shore appears to be used mainly in Australian English, other areas preferring sheared as the standard past tense.

Class 5
The principal parts of the verb metan were:


 * Infinitive: e - metan.
 * Past singular: æ - mæt.
 * Past plural: ǣ - mǣton
 * Past participle: e - meten.

A few Class 5 verbs have i for the infinitive instead, e.g., biddan (bid, as in bid farewell), sittan (sit), and licgan (lie, as in lie down).

In a Class 5 verb, the vowel is followed by a consonant that is neither a liquid nor a nasal (which separates it from a Class 4 verb).

In Middle English, the past tense forms were lengthened, whence the old past tense of speak became spake. However, as for sit, the past tense is sat and no longer sate.

As one can see, the principal parts are nearly identical to those of Class 4, the one exception being the past participle. It is thus not surprising to see why there is a strong tendency for Class 5 verbs to gain strong forms modeled on those of Class 4 verbs; that is, the vowel in the past participle is substituted with o, after which the vowel in the past tense is substituted therewith.

Class 5 has not been preserved well; there is no longer any uniformity in the infinitive vowel, and many surviving verbs have become regular or gained Class 4 strong forms.

Notes:


 * Bid is sometimes conjugated like the Class 2 verb bid (meaning offer) because both verbs have been confused for each other from the similarity in form and meaning.
 * The past tense traditionally rhymes with glad and is occasionally spelled bad (but bade is now the spelling generally used), but an alternative pronunciation has it rhyme with made; both pronunciations are, confusingly, spelled bade.
 * Forbid is not connected to bid of this class, being a derivative of bid of Class 2, but because of the similarity in form and meaning, forbid is now treated as a derivative of bid of Class 5; the past tense is forbade, and the past participle forbidden.
 * Curiously, eat (and its etymological derivative fret) in Old English had lengthened forms for the past tense, even in the singular. However, there must have also been a shortened form, as the shortened form was later lengthened and became ate.
 * The American pronunciation of ate has it rhyme with eight and matches this class's pattern. The British pronunciation, however, traditionally has it rhyme with bet; it seems that this pronunciation rose from vowel shortening, which was applied to weak verbs like lead and read.
 * The past participle of lie, lain, naturally developed from the Old English form; a past participle lien was later formed by analogy, but it is now archaic.

Notes:


 * Reap comes from Old English repan, a Class 5 verb that was a variant of the Class 1 verb rīpan. The original strong verb became ripe and is now used only in a few dialects as a regular verb; if the original verb were still strong, its strong forms would be rope and rippen. As for the variant that became reap, in Old English, it is used far less than rīpan, attested mainly as the inflected form reopaþ, and strong forms appear found only once as rǣpon, the past plural. The strong past participle begins to appear only in Middle English.

Class 6
The principal parts of the verb faran were:


 * Infinitive: a - faran.
 * Past singular: ō - fōr.
 * Past plural: ō - fōron.
 * Past participle: a - faren.

There were some exceptions, as they differed in the infinitive: hebban, hliehhan, sceaþan, scieppan, steppan, and swerian.

On the whole, this class no longer shows any uniformity.

Notes:


 * The past tense forms of draw and slay (and formerly flay and gnaw) appear to have come about from influence of Class 7 verbs, since they would have normally become drough and slough (probably rhyming with bough).
 * The Old English verb sacan (meaning disagree) survives only in the derivative forsake.
 * Stand is noteworthy in that the past tense, stood, has no n in it. The reason is that the n is historically a nasal infix that marks the present tense, whence stood naturally lacks an n. Stand is the only English verb that shows such a feature.
 * Swear looks like a modern Class 4 verb, but in Old English, the past tense was swōr, which matched the past tense forms of other Class 6 verbs. The past participle, interestingly enough, was sworen, which appears to have been made by analogy with Class 4.
 * The strong forms of wake are attested only in the past tense in Old English; oddly enough, the infinitive wacan, present tense forms, and the past participle wacen are unattested. Hence, for the present tense, forms of the weak verbs wæcnan and wæcnian are found instead. In Middle English, the infinitive was waken (which later became wake), and the strong past participle waken. As reflexes of the infinitive are also from OE wacian, the verb was for a long while conjugated weakly, but nowadays, the strong forms are generally used.
 * In OE, the simple verb was used mainly in the sense of come into being (but the sense of become awake is found in awacan). The related weak verb wacian meant stay awake. The two verbs merged into one in Middle English, and the meaning of stay awake was later lost, but it is still found in phrases such as waking hours.
 * The past tense and the past participle of wake (and by extension awake) were later remade by analogy with Class 4 verbs. The original forms would have become wook and waken, as seen in the forms of shake and forsake.
 * The original past participle survives in the adjective awake, in which the n has been dropped from awaken.

Notes:


 * Though hove, the strong form of heave, is no longer found in common speech, it is still used in nautical contexts and the mainly nautical phrase heave in(to) sight/view, e.g., we waited until a ship hove in sight.
 * Hove is not the usual development of the Old English form, as it would have become hoove instead. As the past participle became hoven at one point, it suggests that hove and hoven are forms made by analogy with verbs that had Class 4 forms.
 * Heft was an irregular form made by analogy with verbs like leave and cleave, but it is no longer used.
 * The standard pronunciation of laugh comes from a variant using /f/. If the past tense lough (OE hlōh) had not become obsolete and had changed likewise, it would rhyme with tough (OE tōh).
 * Shapen and shaven are still used as adjectives.
 * Wash was conjugated in Old English mainly like a Class 6 verb, though one instance of a Class 7 past tense form (wēox, the last consonant due to metathesis) appeared.

Class 7
This is not so much a class as it is a category for all the verbs whose past tense was formed by reduplication in Proto-Germanic. Therefore, there was no uniformity in the infinitive vowel. The past tense, however, had ē or ēo, and the past participle had the same vowel as was in the infinitive, the lone exception being wēpan (weep).

Subclass 1
There is an obvious pattern in these surviving Class 7 verbs, so these are classified as a subclass. This subclass has suffered a few losses, but it has held up rather well.

Notes:


 * Blow in the usual meaning of move through air has the same form as the verb blow meaning produce flowers. Etymologically, in Old English, both verbs belonged to Class 7 and shared the same past tense forms, though their past participle forms differed.

Notes:


 * The past tense crew is occasionally used when the verb is used to describe a cock's characteristic cry, but crow is now generally conjugated regularly.

Subclass 2
This subclass consists of the remaining Class 7 verbs. Unsurprisingly, there is no uniformity among them at all.

Strong verbs currently used in standard speech

Notes:


 * Oddly enough, the past tense of beat is spelled not as beet (from OE bēot) but as beat (beat and beet were formerly pronounced differently); it may be that that the infinitive and the past participle (which had the expected form, beaten) influenced the past tense form.
 * The phonetic history of hang is somewhat complicated. Originally, there were two verbs in Old English: the strong verb hōn and the weak verb hangian. The first and third person past indicative of the strong verb was hēng, and the past participle was gehangen. Hence, the strong verb's past participle and the weak verb's infinitive helped establish hang as the infinitive form later on, and the past tense naturally became hing later (e regularly changes to i before ng). Moreover, the Old Norse verb hengja came into northern dialects, whence those dialects used hing as the infinitive instead of hang. By analogy with Class 3 verbs like sing, hang was used as a past tense, and hung was formed by analogy. Hung later entered standard speech, whence the current conjugation is hang, hung, hung.
 * The old past participle of hold is found in the adjective beholden, which has a different meaning from that of behold now.

Notes:


 * Even in Old English, read had already come to be used as a weak verb; seldom did the strong forms appear.
 * The old past participle of sough survives in a by-form as swoon, which is now a verb whose meaning has diverged greatly from that of sough. The original past participle would have likely become sown, rhyming with town.
 * The verb itself varies in its pronunciation, since it is not a commonly used word. The two acceptable pronunciations have it rhyme with either now or stuff, though by analogy with the old past participle form, the pronunciation rhyming with now likely would have become the only acceptable standard pronunciation.
 * Wax was, in Proto-Germanic, a strong verb of Class 6, but in the West Saxon dialect of Old English, it came to be conjugated like a Class 7 verb; the old past tense form, wōx (found in awōx, the past tense of aweaxan), was confined to the Northumbrian dialect.

Weak verbs made strong
There are some weak verbs that have become strong by analogy.

Notes:


 * The past tense of Old English hȳdan was hȳdde, which naturally became hid. But hide was later felt to be a strong verb by analogy with Class 1 verbs like slide and bite, so the strong past participle hidden was formed, overthrowing the weak past participle.
 * The same process appears to have happened for chide. Interestingly enough, even though chide formerly had chode as an analogical past tense, hide does not seem to have ever developed hode by analogy.
 * Dig and stick are grouped with Class 3-1 verbs, though they do not end with a nasal consonant. It is noteworthy that they both end with velar consonants.
 * The history of the strong forms of stick is somewhat complicated; originally, in Middle English, it formed strong forms by analogy with Class 4 verbs, and these forms are the ones used today. But there was also another verb, ME steken, which had strong forms based on Class 5 and with which stick had been often confused. In the end, ME steken became disused in standard speech, and stick ended up using stuck as the past tense and the past participle.
 * Stuck seems like a form analogical to Class 3-1 forms such as stung and clung, and it is certainly now interpreted as such, but according to Hereward Thimbleby Price, it seems likelier that it was a natural development of variants of the older Class 4 forms, stoke and stoken, and such development can be found in blood and flood.
 * Get itself is a borrowing from Old Norse geta, which was also a Class 5 verb, but the native cognate is attested in derivative words in Old English and would have become yet, whence the uninfluenced forms of forget and beget would be foryet and beyet.
 * Give is from Old Norse, since the native form would have become yeave.
 * The archaic past tense of show, shew, is not to be confused with shew, an archaic spelling of show.
 * Though showed is used for the past participle by some people, the much preferred form is now shown.
 * String gained strung as its past tense and past participle; the past tense form strang was formed much later and is used only in some dialects.

Notes:


 * Dive and sneak are the best known examples of recent irregularization of verbs.
 * Around the 19th century, dive became strong by analogy with verbs of this class and gained the past tense form dove, which is now widespread in American English (though dived is still common and always acceptable). Those who use dove as the past tense of dive keep dived as the past participle, however.
 * Sneak has snuck as an inflected form in American English (though sneaked is still common and always acceptable), but the root thereof is not certain, since there is no clear analogy for the shift from sneaked to snuck.
 * Proven was formed from preve, an alternate form of prove that was used in Middle English. Preve died out in standard speech, but survived in Scotland, and proven first appeared in Scottish legal contexts. The Scottish pronunciation has proven rhyme with woven, but in all other areas, because prove is used as infinitive, the vowel was changed to match the infinitive's. Hence, it looks as if it had been formed by analogy with verbs like hew.
 * The past participle is used only for the base verb and disprove; approve, though etymologically related to prove, is conjugated regularly.
 * In Old English, there was a weak verb spǣtan, which meant the same thing as spit and whose past tense was spǣtte. The past tense naturally became spat, which was later reinterpreted to be the past tense of spit by analogy with the Class 5 verb sit, and the original verb whence spat was gotten became obsolete. A past participle spitten was later formed, but it is now dialectal.
 * Strive may be found as a regular verb, but traditionally, the strong forms are preferred.

Notes:


 * The Old English weak verb rignan (meaning rain) had rīnan as a variant, whence came the analogous past tense rān (which is attested only once; the analogous past participle is unattested). In Middle English, the verb became rinen, and the past tense rone (the weak past tense died off in early Middle English); it is a rare instance of an Old English weak verb's conversion to a strong verb. As for the verb, it died off in the 15th century.
 * The following regular verbs gained strong forms in Middle English, but these forms are no longer used (except possibly in some dialects):
 * Arrive (French) - past tense: arrove, past participle: arriven.
 * Ding (as in strike, possibly Norse) - past tense: dang, past participle: dung.
 * Quake - past tense: quook. The analogous past participle, quaken, is unattested.
 * Snow - past tense: snew, past participle: snown.
 * Occasionally, in poetry and older usage, -en is used instead of ed to form a past participle with weak verbs, e.g., wreathen, paven, loaden (by analogy with laden), rotten (truly a Scandinavian loanword and only an adjective in modern standard speech).

Modern grouping of strong verbs
Obviously, it is no longer apparent that all these different strong verbs once belonged to seven different classes. From a modern point of view, the strong verbs can be grouped differently. Standard American pronunciation is used.

Mixed verbs (verbs that have either a past tense or a past participle that is clearly not strong):

The overall changes are:


 * Consonantal differences between the infinitive and inflected forms have been thoroughly wiped out.
 * OE drīfan had [v], but drāf, the past singular, had [f] instead. The reason is that [v] was simply an allophone of /f/ in Old English. Later on, [f] and [v] became treated as separate phonemes, and so the consonant in the past tense form was changed to conform with that in the infinitive.
 * OE frēosan shows a seemingly odd consonantal difference in frure (the past plural) and froren (the past participle). The reason for this is due to Verner's law. Of course, later on, this difference was done away with, and so we now use frozen rather than frorn as the past participle.
 * The initial consonant for some strong verbs differed because of palatalization. For example, OE ceorfan showed /tʃ/, but the past plural curfe and the past participle corfen showed /k/ instead. Later on, for this verb, the unpalatalized forms came to influence the infinitive, whence the verb is now carve rather than charve. For OE gieldan (yield), however, the old strong forms were influenced by the consonant in the infinitive, and so the strong past participle became yolden before becoming archaic.
 * The past tense no longer show a difference in number. Hence, sang (previously the past singular only) came to be used for the past plural as well.
 * For the second-person singular (thou), the past tense formerly did not use the characteristic second-person singular suffix -est; in OE, the past tense of singan for the second-person singular was sunge (sharing the same vowel as the past plural). Later on, however, because of the strong association between thou and -est, the past tense of all strong verbs came to use -est. Hence, the past tense form became sangest.

Archaic, dialectal, or obsolete verbs
Notes:


 * The dialectal verbs sie, thee, and wry were, in Old English, sēon, þēon, and wrēon, all of which were contracted verbs that originally had the same vowel as this class's other verbs and were often conjugated like Class 2 verbs because of the new infinitive vowel. OE sēon and wrēon would have normally become see and wree, but they were influenced by their other forms.
 * Sike, now a dialectal word meaning sigh, gained the irregular weak form sight by analogy with verbs like teach and buy. Sigh is likely a back-formation from sight (which form is now obsolete).

Notes:


 * The obsolete verb leese (OE lēosan) is now found only in the adjective forlorn, which is the past participle of forlese (forsake) and was affected by Verner's law. If the verb had stayed in regular use, the strong forms would have likely been changed by analogy and would have become loze and lozen.
 * The irregular verb lose is generally derived from Old English losian, but some trace it back to OE lēosan instead. The explanation is that as cēosan and scēotan became choose and shoot from altered stress of the diphthong, so did lēosan become lose; normally, cēosan and scēotan would have yielded cheese and sheet. This shift in stress is also seen in words such as show (OE scēawian), troth, originally a variant of truth (OE trēowþ), and hoo, a dialectal variant of she from OE hēo.

Notes:


 * The dialectal verb frain is from Old English frignan, which also had byforms because the g often disappeared. One byform was frīnan, which was partly conjugated like a Class 1 verb.
 * Though swelt is no longer used in the standard speech, it lives on in the frequentative verb swelter.
 * The archaic verb worth is still used in the literary phrase woe worth (wherein worth is subjunctive, and the phrase thus means woe be to). If the verb had survived in spoken speech, it would be pronounced /wərð/, since as a verb passed down from Old English, the dental fricative would naturally be voiced.

Notes:


 * The dialectal verb heal began to be conjugated regularly in Middle English, mainly because the strong verb helan had merged with the weak verb helian.
 * The past participle of nim lives on in the adjective numb (the b is unetymological and not pronounced, and the past participle ending -en has been dropped). The old past participle (OE numen, often spelled as nomen in Middle English) had the same vowel as in come (OE cuman, past participle cumen).
 * In OE, niman had a variety of forms for the past tense. One form was nam, which was etymologically the original form. Another form was nōm, which came about by analogy with the plural form nōmon.
 * Nim, by some later writers, was conjugated like a weak verb, since by that point, the verb had fallen out of common use. If the strong forms had survived, they would have likely become nam and num, since it would have also been strengthened by analogy with Class 3-1 verbs.

Notes:


 * As for the obsolete verb queath (the verb lives on in the derivative bequeath), the past tense became quoth (which lives on as a literary word for said) from a few different phonetic causes. However, bequeath (the only derivative in which the root verb survives) was later regularized, and so the past tense is no longer bequoth.
 * The current pronunciation of quoth is artificial, since it is a literary word, and the spelling suggests that it is pronounced /kwoʊθ/. However, since it is the past tense of a verb inherited from Old English, a more natural pronunciation would be /kwoʊð/.
 * The rare past participle quothen is attested only in bequothen, which did not live past Middle English.
 * Yet was used only in derivatives in Old English, and the unprefixed verb get came from Old Norse. There are a few instances of yet used without a prefix in Old English, but they are likely shortened forms of prefixed verbs rather than a genuine survival of the base verb. In Middle English, there are also a few instances of lone yet, but they are likely the Norse verb influenced by derivatives. Perhaps even without the introduction of the Norse verb, the base verb yet would have been coined as a backformation from a prefixed verb such as beyet, which formerly meant obtain. This kind of backformation has happened before, as seen in gin, an obsolete variant of begin.
 * On the whole, yet shows Class 5 forms; seldom were there forms based on Class 4 forms, and even in those instances, they were likely from influence of the Class 4 forms of get.
 * The Old English word for be had wesan as one of its infinitives. As wesan was originally a Class 5 verb, the current past tense forms (was and were) are based on Class 5's pattern.
 * That the past indicative forms show an s/r difference is due to Verner's law, and be is the only current verb that shows a noticeable consonantal difference in the past tense with regard to number. Verner's law also explains why were is used for the singular in the past subjunctive.
 * In Middle English, the verb steken (which meant pierce) was conjugated like a Class 5 verb. It is attested no earlier than that, and so it may have come from an unattested Old English verb stecan; at the very least, it is Germanic and akin to German stechen and Dutch steken. It was often confused with the verb stick, and so the strong forms were also mixed up with the Class 4 strong forms of stick.

Notes:


 * Graven and laden are still used as adjectives.

Notes:


 * The latest form of the strong past tense of the dialectal verb fang was feng, which would have become fing later. Fang and hang were also parallel in conjugation in Old English, both verbs being contracted verbs.
 * The same would have also happened for the dialectal verb gang; the latest past tense form was geng (from which we would have gotten ging), though gang was not parallel in conjugation with hang and fang in Old English.