Grammar guide The rule
Stem-changing verbs in Spanish (e→ie, o→ue, e→i)
In some Spanish verbs the stressed vowel of the stem changes: querer becomes quiero, poder becomes puedo. The endings stay regular.
The three changes
The change happens only where the stress falls on the stem.
- e → ie
- querer, pensar, empezar, preferir The e of the stem becomes ie. quiero, quieres, quiere, queremos, queréis, quieren
- o → ue
- poder, dormir, volver, encontrar The o becomes ue; jugar changes u to ue. puedo, puedes, puede, podemos, podéis, pueden · juego
- e → i
- pedir, servir, repetir, seguir Only -ir verbs make this change. pido, pides, pide, pedimos, pedís, piden
- The boot
- Nosotros and vosotros stay regular Their stress falls on the ending. In the preterite, -ir verbs change e→i and o→u in the third person only. podemos · pidió, pidieron · durmió, durmieron
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