Stem-changing verbs – Spanish basics

In many common verbs the last vowel of the stem changes when it's stressed: e becomes ie, o becomes ue, or e becomes i. The stress falls on the stem in every present form except "we" and "you all", so those two keep the infinitive's vowel.

	e → ie querer	o → ue poder	e → i pedir
yo	quiero	puedo	pido
tú	quieres	puedes	pides
él, ella, usted	quiere	puede	pide
nosotros	queremos	podemos	pedimos
vosotros	queréis	podéis	pedís
ellos, ellas, ustedes	quieren	pueden	piden

The endings are regular; only the stem changes. Dictionaries often show the change: querer (ie).

Change	Common verbs
e → ie	querer want, pensar think, empezar begin, cerrar close, entender understand, preferir prefer, sentir feel
o → ue	poder can, volver come back, dormir sleep, encontrar find, contar count, tell, costar cost, recordar remember
e → i	pedir ask for, servir serve, repetir repeat, seguir follow, go on
u → ue	jugar play, the only one

¿Quieres un café?
Do you want a coffee?
No puedo ir.
I can't go.
¿Cuánto cuesta?
How much does it cost?
Siempre pido lo mismo.
I always order the same thing.
Los niños juegan en el parque.
The children are playing in the park.

The change can't be seen in the infinitive: entender changes, aprender doesn't. Learn it with each verb.

Cards from this guide