Verb Forms & Past Tense

English has roughly 200 irregular verbs still in everyday use — a small, closed list left over from a much bigger system that used to run the whole language. This hub explains what "irregular" actually means here, why the list stopped growing centuries ago, why it keeps shrinking rather than growing, and where to find each verb's own conjugation page.

What "irregular" means

A regular English verb takes -ed for both its simple past and its past participle: walk becomes walked, walked. An irregular verb changes some other way — a vowel shift (sing, sang, sung), a consonant change (bring, brought, brought), or no change at all (cut, cut, cut). Roughly 200 of these survive in modern English, and they are disproportionately the verbs you use every day: be, have, do, go, say, get, make, know, think, take, see, come. Frequency is exactly why they stayed irregular — see the history section below. Verbs coined or borrowed into English in the last few centuries are, without exception, regular: "google," "text," and "photobomb" all take -ed, because the -ed rule is the language's productive default and irregularity is not something new verbs acquire.

Where these verbs come from

Most English irregular verbs descend from the Germanic "strong verb" system, which marked tense with an internal vowel change (called ablaut) instead of a suffix — the same mechanism still visible in German singen/sang/gesungen and English's own sing/sang/sung. Old English had seven classes of strong verbs, each with its own vowel pattern; that system has been eroding for over a thousand years as new verbs entering the language default to the regular -ed pattern instead. A smaller second group of irregulars comes from Old English "weak" verbs that took a dental suffix (-t or -d) but altered the stem too, which is why you get keep/kept and buy/bought rather than a clean stem-plus-ed. A third, much smaller group is suppletive: the past tense is borrowed from a totally different verb rather than built from the present-tense stem at all, the clearest case being go/went, where "went" started life as the past tense of a separate, now largely forgotten verb, "wend." "Be" takes suppletion even further, welding together pieces of several distinct ancient roots into one working paradigm — a case detailed on its own page.

Why they haven't regularized

Linguists who study language change (notably a widely cited study by Erez Lieberman and colleagues, published in Nature in 2007, which tracked the regularization of English verbs across a thousand years of text) found that how fast a verb regularizes is tied directly to how often people use it: rare irregular verbs regularize fastest, common ones survive almost indefinitely because speakers hear and produce their irregular forms constantly enough to keep them memorized rather than defaulting to the regular rule. Their model estimated that a verb used 100 times less frequently than another regularizes roughly ten times as fast. That's why obscure irregulars like "chide" (chid/chidden) or "cleave" (clove/cloven) have mostly regularized or gained regular alternatives in modern usage, while "be," "have," "go," and "say" — among the most frequent verbs in the language — show no sign of change and likely won't within any of our lifetimes.

The verbs that are actively changing right now

Not every entry on this site's past-tense list is settled. A visible middle group is mid-regularization: dreamed and dreamt, learned and learnt, spelled and spelt, burned and burnt, leaped and leapt are all genuinely accepted variants today, with the -ed form now dominant in American English and the -t form more common in British English — a live regional split rather than a right-and-wrong situation. "Dived" and "dove" show the opposite direction: dive was historically a regular weak verb (dived), but "dove" spread through analogy with strong verbs like drive/drove starting in 19th-century North American usage and is now the more common past tense in American English, while British English has stayed with "dived." These pages call out that live variation explicitly rather than picking a single "correct" answer where usage genuinely hasn't settled.

Prefixed and compound verbs

A large share of the 200 verbs on this hub aren't base verbs at all but prefixed compounds built on an irregular root: understand, withstand, and stand all share stand's irregular pattern (stood); overthrow, forgo, and undergo all inherit go's (went, gone); mistake, undertake, and partake all inherit take's (took, taken). This is mechanical, not coincidental — English productively builds new verbs by prefixing an existing one (over-, under-, mis-, out-, with-, re-), and the resulting compound always conjugates exactly like its root, which is why "outrun" is outran/outrun rather than a regular "outran-ed." Recognizing the root inside a compound verb you don't recognize (like "gainsay," built on "say") is usually the fastest way to guess its correct past tense without looking it up.

Defective verbs: the modals that never conjugate normally

A separate, much smaller group of verbs isn't irregular so much as incomplete: can, could, may, might, shall, should, will, would, and must have no infinitive form (nobody says "to can"), no -ing form, no third-person -s ("she can," never "she cans"), and in several cases no distinct past tense at all — "must" is used for both present and past obligation, borrowing "had to" to fill the gap. This isn't decay or error; it's a fossil of a separate Old English verb class (the "preterite-present" verbs), whose present-tense forms originally looked like past tenses of ordinary strong verbs and simply never developed a full conjugation to go with them. "Could," "should," and "would" still carry a silent "l" that was pronounced in Middle English (spelled to match "can," "shall," and "will" by analogy, not because it reflects any sound actually made in speaking) — one of the clearer cases where modern spelling fossilizes a pronunciation nobody uses anymore rather than reflecting current speech.

British vs. American irregular spellings

Several irregular verbs split cleanly along the British/American line, and "gotten" is the case people are most surprised by: American English kept the old past participle "gotten" (I have gotten better), while British English lost it almost everywhere except frozen phrases like "ill-gotten gains," using plain "got" for both past simple and past participle instead. That's the reverse of what most people assume — American English is usually taken to be the newer, more "simplified" variety, but here it's British English that dropped an older form and American English that preserved it. The same regional split shows up across a cluster of verbs where the -t ending is the older British-preferred form and -ed the newer, now-dominant American one: learnt/learned, spelt/spelled, spoilt/spoiled, burnt/burned, dreamt/dreamed, leapt/leaped. None of these represents a right-and-wrong pair; each verb's own page states which region prefers which form rather than picking one as the "correct" answer.

Phrasal verbs inherit their root's irregularity

English builds an enormous number of verbs by pairing a base verb with a preposition or adverb to create a new, often idiomatic meaning — give up, break down, take off, run into, come across — and every one of these phrasal verbs conjugates exactly like its base verb, no exceptions. "Give up" is irregular precisely because "give" is (gave up, given up); "break down" follows "break" (broke down, broken down); "run into" follows "run" (ran into, run into). This matters practically because phrasal verbs are often learned as fixed idiomatic chunks rather than as "verb + particle," which can obscure the fact that the conjugation rule was never actually new — a learner who already knows "take" is irregular (took, taken) doesn't need to separately memorize that "take on," "take off," "take over," and "undertake" are irregular too; recognizing the shared root does that work automatically, the same shortcut described above for prefixed compounds like "understand" and "overthrow."

"Be": the most irregular verb in the language

"Be" isn't just irregular, it's suppletive in the extreme — its forms (am, is, are, was, were, been, being) come from at least three separate ancient verb roots welded into a single working paradigm, rather than one root undergoing sound changes the way "sing"/"sang"/"sung" does. "Am" and "is" descend from one Indo-European root, "are" from a second (originally a Northern English and Old Norse-influenced form that later displaced the Old English equivalent), and "was"/"were" from a third root entirely, related to a verb meaning "to remain" or "to dwell." No other English verb spreads its forms across this many unrelated historical sources, which is exactly why "be" resists every attempt to explain its irregularity with a single tidy rule the way most other irregular verbs on this hub can be traced to one specific historical cause.

How to use this hub

Each verb's own page states the correct simple-past and past-participle forms in the first line, then explains the specific historical reason that verb is irregular — which strong-verb class it descends from, whether it's suppletive, or whether it's one of the still-shifting dreamed/dreamt-style pairs — along with real example sentences and a memory trick tailored to that verb specifically. Use the A-Z index for the full 200-verb list, or browse by the patterns described above if you're trying to learn the system rather than look up one word at a time.

Pages in this hub (246)

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