Verbs with a broken stem: llueve, muerde, florezco

A Spanish verb changes not only at the end. In a good hundred verbs, when the stress lands on the stem, the vowel in it splits in two — and the infinitive gives no hint of it: llover gives llueve, morder — muerde, nevar — nieva. These are not one-off exceptions but three regular rows, and half of this wave's weather and nature words sit in them. For example: “Está lloviendo y en el norte hasta nieva” — It's raining…

Updated September 1, 2026 · Lingofly

How it works

A Spanish verb changes not only at the end. In a good hundred verbs, when the stress lands on the stem, the vowel in it splits in two — and the infinitive gives no hint of it: llover gives llueve, mordermuerde, nevarnieva. These are not one-off exceptions but three regular rows, and half of this wave's weather and nature words sit in them.

Row one, o → ue: poder → puedo, volver → vuelvo, morder → muerdo, llover → llueve, acordarse → me acuerdo, esforzarse → me esfuerzo. Row two, e → ie: querer → quiero, nevar → nieva, preferir → prefiero, empezar → empiezo, pensar → pienso. Row three, e → i, only in -ir verbs: pedir → pido, medir → mido, repetir → repito, seguir → sigo.

The stem breaks not everywhere, but exactly where the stress falls on it: in the 'we' and 'you plural' forms the stress moves to the ending and the stem returns whole. Puedo, puedes, puede, podemos, podéis, pueden — four forms with 'ue' and two without. English has nothing like it — its vowels change unpredictably (sing, sang, sung) — while the Spanish pattern is regular: the four outer forms change, the middle two stay as in the infinitive. Learners call it the boot rule.

A separate troop: verbs in -cer and -cir grow a 'z' in the 'I' form. Conocer → conozco, florecer → florezco, nacer → nazco, conducir → conduzco, traducir → traduzco. Nothing happens in the other persons.

And the smallest troop — the impersonal weather verbs. Llover, nevar, granizar, tronar, amanecer, anochecer have only a third person singular: llueve, nieva, graniza, amanece. Yo lluevo is impossible even as a joke — these verbs have no subject at all. They do take estar willingly, though: está lloviendo, está granizando.

Table

Verbs with a broken stem: llueve, muerde, florezco
rowinfinitiveyonosotroswhat to remember
o → uemordermuerdomordemosthe middle does not change
o → uelloverlluevethird person only
e → ienevarnievano subject exists
e → ieempezarempiezoempezamosthe stress decides
e → i (-ir)medirmidomedimos-ir verbs only
-cer / -cirflorecerflorezcoflorecemosz only in the yo form
-circonducirconduzcoconducimossame as nacer, conocer

By example

  • Está lloviendo y en el norte hasta nieva
    It's raining, and in the north it's even snowing
  • Los almendros florecen pronto, pero yo no florezco hasta mayo
    Almond trees blossom early, but I do not blossom until May
  • Cuidado con el perro, que muerde; nosotros no mordemos
    Careful with the dog, it bites; we do not bite

How the rule settles in your head

A rule is not memorized from an explanation. It is memorized from an attempt to use it and a mistake — that is why the app delivers it mixed in with words, not as a separate lesson: it resurfaces exactly where you forgot it.

Frequently asked

Verbs with a broken stem: how does it work in Spanish?

A Spanish verb changes not only at the end. In a good hundred verbs, when the stress lands on the stem, the vowel in it splits in two — and the infinitive gives no hint of it: llover gives llueve, morder — muerde, nevar — nieva. These are not one-off exceptions but three regular rows, and half of…

What does it look like in an example sentence Spanish?

“Está lloviendo y en el norte hasta nieva” — It's raining, and in the north it's even snowing. A rule is easier to test on sentences like this than to memorize as a wording: what surfaces in conversation is the sentence.

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