Most irregular verbs are irregular in company. Learn the family and you have covered every verb in it.
In these verbs the stem vowel changes only where the stress falls on the stem: yo, tú, él and ellos. Nosotros and vosotros are stressed on the ending, so they keep the original vowel. The changes are most visible in the Presente and the Presente de subjuntivo.
Verbs in -ar and -er, such as pensar and querer.
Example: pensar
Verbs in -ar and -er, such as contar and poder.
Example: contar
Verbs in -ir only, such as pedir and servir. The change is wider than in the other families.
Example: pedir
The Imperfecto de subjuntivo and Futuro simple de subjuntivo follow the Indefinido too: pidiera, pidiere.
Verbs in -ir with a second change, such as sentir, dormir and morir.
ie / uei / ufirst and second change
Example: dormir
The second change also reaches the Imperfecto de subjuntivo, the Futuro simple de subjuntivo and the gerund: durmiera, durmiere, durmiendo.
Only a few verbs change this way.
Example: jugar
Example: adquirir
These families cover whole groups of verbs, so learning the pattern covers many of them at once.
Only the yo form of the Presente is irregular in these verbs: -go, -zco and a few others.
The yo form becomes the stem of the whole Presente de subjuntivo:
Exceptions: ser (sea), ir (vaya), estar (esté), saber (sepa), dar (dé) and haber (haya).
A different stem and special endings with no written accents.
| uv- | tener (tuve), estar (estuve), andar (anduve) |
|---|---|
| u- | poder (pude), poner (puse), saber (supe), caber (cupe), haber (hube) |
| i- | querer (quise), hacer (hice), venir (vine) |
| j- | decir (dije), traer (traje), conducir (conduje) |
The endings are -e, -iste, -o, -imos, -isteis, -ieron, and -eron after j. The same stem builds the Imperfecto de subjuntivo and the Futuro simple de subjuntivo: tuviera, tuviere, dijera, dijere.
The endings are the regular ones; only the stem changes, and both tenses share it.
| drops a vowel | poder → podr-, saber → sabr-, caber → cabr-, haber → habr-, querer → querr- |
|---|---|
| adds a d | tener → tendr-, poner → pondr-, salir → saldr-, venir → vendr-, valer → valdr- |
| shortens | hacer → har-, decir → dir- |
The sound stays regular; the spelling adapts to keep it.
| -car | c → qu: buscar → busqué, busque |
|---|---|
| -gar | g → gu: pagar → pagué, pague |
| -zar | z → c: empezar → empecé, empiece |
| -guar | gu → gü: averiguar → averigüé, averigüe |
| -ger, -gir | g → j: coger → cojo, coja; elegir → elijo |
| -guir | gu → g: seguir → sigo, siga |
| -eer, -aer, -oír, -uir | i → y: leer → leyó, leyeron; caer → cayó; oír → oyó; construir → construyó |
Changes before e show up in the yo form of the Indefinido and throughout the Presente de subjuntivo. Changes before o and a show up in the yo form of the Presente and, again, throughout the Presente de subjuntivo. The Imperativo forms built on the subjunctive follow. The i → y change affects the él and ellos forms of theIndefinido and the forms built on them.