Irregular Gerunds

Most Spanish gerunds are perfectly regular, but two groups of verbs require extra attention: stem-changing -ir verbs and verbs whose stem ends in a vowel. Both groups follow predictable patterns, so once you recognize them, the irregular gerunds become easy to produce.

Stem-Changing -ir Verbs

Only -ir verbs with a stem change in the present tense also change their stem in the gerund. The change is always the same pattern:

  • e becomes i
  • o becomes u

Then the normal ending -iendo is added.

InfinitiveMeaningStem changeGerund
dormirto sleepo → udurmiendo
morirto dieo → umuriendo
pedirto ask fore → ipidiendo
servirto servee → isirviendo
repetirto repeate → irepitiendo
seguirto followe → isiguiendo
sentirto feele → isintiendo
mentirto liee → imintiendo
venirto comee → iviniendo
decirto saye → idiciendo
preferirto prefere → iprefiriendo

Los niños están durmiendo en el cuarto de al lado.

The kids are sleeping in the next room.

Ella está pidiendo un café con leche.

She is ordering a coffee with milk.

Estoy viniendo de la oficina ahora mismo.

I am coming from the office right now.

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The rule is specific: only -ir verbs do this. -Ar and -er stem-changers keep their stem intact in the gerund. Pensar becomes pensando (not pinsando), and volver becomes volviendo (not vulviendo).

Vowel Stems: -iendo Becomes -yendo

When the stem of an -er or -ir verb ends in a vowel, the -i- of -iendo is caught between two vowels. Spanish spelling rules turn that unstressed i into a y, producing -yendo.

InfinitiveMeaningStemGerund
leerto readle-leyendo
creerto believecre-creyendo
caerto fallca-cayendo
traerto bringtra-trayendo
oírto hearo-oyendo
huirto fleehu-huyendo
construirto buildconstru-construyendo
destruirto destroydestru-destruyendo
incluirto includeinclu-incluyendo
irto goyendo

Mi papá está leyendo el periódico en la sala.

My dad is reading the paper in the living room.

Están construyendo un edificio enorme en la esquina.

They are building a huge building on the corner.

El ladrón salió huyendo por la puerta trasera.

The thief ran off through the back door.

A Special Case: Poder

The verb poder (to be able to) has an irregular gerund too: pudiendo. Notice it follows the o to u pattern even though poder is an -er verb, not -ir. It is one of the few non--ir verbs to change its stem in the gerund, and it appears mostly in adverbial constructions rather than with estar.

No pudiendo resolver el problema solo, llamó a un amigo.

Not being able to solve the problem alone, he called a friend.

Putting It Together

The good news is that these two patterns cover almost every irregular gerund you will meet. Regular verbs take -ando or -iendo, stem-changing -ir verbs raise their vowel, and vowel-stem verbs write -yendo. Everything else is regular.

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When in doubt about a specific verb, check its present-tense conjugation. If it is an -ir verb with an e to ie, e to i, or o to ue change, the gerund will use the raised vowel (i or u). See also Irregular Gerunds in the Present Progressive for these forms in context.

Next, look at Gerund Usage and Restrictions to see how these forms are used and, just as important, where Spanish does not allow a gerund at all.

Related Topics

  • Gerund FormationA2Build the Spanish gerund by adding -ando to -ar verbs and -iendo to -er and -ir verbs, always invariable.
  • Gerund Usage and RestrictionsB1The Spanish gerund describes actions in progress or adverbial manner but cannot be used as an adjective, a noun, or after prepositions.
  • Irregular GerundsA2Stem-changing -ir verbs and verbs with a vowel before the ending form special gerunds like durmiendo, pidiendo, and leyendo.