The pattern rule

When the stressed syllable contains the stem vowel o, it changes to ue. Like e→ie verbs, this affects yo, tú, él/ella, and ellos/ellas in the present tense, but NOT nosotros or vosotros.

💡 Tip The verb dormir is a special case — it changes o→ue in the present tense but o→u (not ue) in the preterite third person: durmió, durmieron.

Example: poder (to be able to / can) — Present

Irregular forms are highlighted in red. Regular forms for comparison are shown in grey where they differ.

Pronoun Actual form Regular would be
yo puedo* podo
puedes* podes
él/ella puede* pode
nosotros podemos
vosotros podéis
ellos/ellas pueden* poden
See full conjugation of poder →

Frequently asked questions

What are o to ue stem-changing verbs in Spanish?

O to ue stem-changing verbs change the stem vowel o to ue when it is stressed. In the present tense this affects yo, tú, él/ella, and ellos/ellas. Examples include poder (puedo), volver (vuelvo), and dormir (duermo).

Is the verb jugar an o to ue verb?

No — jugar is a u→ue stem-changing verb (juego, juegas, juega...). It follows the same pattern as o→ue verbs but changes u to ue instead. It is the only common u→ue verb in Spanish.

Do o to ue verbs change in the preterite?

Most o→ue verbs are regular in the preterite. The exceptions are dormir and morir, which change o→u (not ue) in the third-person preterite: durmió, durmieron; murió, murieron.

All 39 o → ue verbs — ordered by frequency

Sorted by how commonly each verb appears in everyday Spanish. Start with rank #1 and work down.

Other irregular verb patterns

Practise these verbs with spaced repetition to actually remember them.