You sit down in a café in Bogotá. The waiter asks, "¿Qué quieren?" You answer, "Quiero un café y mi amigo pide un té. ¿Puedo pagar con tarjeta?" Three of the most useful verbs in that exchange, querer, pedir and poder, all change a vowel in the middle. The endings are the regular ones you already know. Only the stem shifts.
Level: A1.
What changes, and where
Take the infinitive, remove -ar, -er or -ir, and you have the stem: quer-, pod-, ped-. In a stem-changing verb, the last vowel of that stem changes in some forms of the present tense:
- e→ie: querer → quiero
- o→ue: poder → puedo
- e→i: pedir → pido
Then you add the normal present-tense endings.
The boot pattern
Write the six forms in a table, two columns by three rows, and draw a line around the ones that change. The shape looks like a boot.
| singular | plural | |
|---|---|---|
| 1st person | quiero | queremos |
| 2nd person | quieres | queréis |
| 3rd person | quiere | quieren |
Yo, tú, él/ella/usted and ellos/ellas/ustedes change. Nosotros and vosotros keep the original vowel. The reason is stress: the change happens in the stressed syllable, and in queremos and queréis the stress moves onto the ending.
In Latin America, ustedes is the plural "you" for everyone, and it's inside the boot: ustedes quieren. Vosotros is used in most of Spain. If you learn voseo (vos, common in Argentina, Uruguay, Paraguay and parts of Central America), note that vos forms don't change either: vos querés, vos podés.
e→ie
- querer (to want): quiero, quieres, quiere, queremos, queréis, quieren
- pensar (to think): pienso
- empezar (to start): empiezo
- entender (to understand): entiendo
- preferir (to prefer): prefiero. When the stem has two e's, the second one changes.
Tener and venir also take e→ie, but their yo forms (tengo, vengo) are irregular, so they live in the irregular-verbs deck.
o→ue
- poder (can, to be able to): puedo, puedes, puede, podemos, podéis, pueden
- dormir (to sleep): duermo
- volver (to come back): vuelvo
- encontrar (to find): encuentro
After poder, the next verb stays in the infinitive: "No puedo dormir" (I can't sleep).
e→i
This change only happens in -ir verbs.
- pedir (to ask for, to order): pido, pides, pide, pedimos, pedís, piden
- servir (to serve): sirvo
- repetir (to repeat): repito
In a classroom you'll hear "¿Puede repetir, por favor?" (Can you repeat that, please?). Both verbs are stem-changers, but only puede shows it: repetir stays in the infinitive.
jugar: u→ue
Jugar is the only common verb that changes u→ue: juego, juegas, juega, jugamos, jugáis, juegan. Spain says "jugar al fútbol"; in much of Latin America you'll also hear "jugar fútbol".
Mistakes learners make
- Changing nosotros. "Puedemos" and "quieremos" are wrong. Podemos, queremos.
- Changing every verb with an e or o. Comer, beber and comprar are regular. Learn each verb with its change, the way word lists mark it: dormir (ue), pedir (i).
- Using the wrong change. Pedir is e→i, so "piedo" is wrong. Pido.
- Changing the wrong vowel. Preferir → prefiero, not "priefero".
- Changing the ending instead of the stem. The endings are regular: duermen, not "duerman" (that's a different form you'll meet later).
Frequently asked questions
What are stem-changing verbs in Spanish?
Verbs whose stem vowel changes in the stressed forms of the present tense: e→ie (querer), o→ue (poder), e→i (pedir), plus jugar u→ue. The endings stay regular.
Why is it called the boot verb pattern?
If you write the six forms in a two-column table, the four that change form the shape of a boot. Nosotros and vosotros sit outside it.
How do I know if a Spanish verb is stem-changing?
You can't tell from the infinitive alone, so learn each verb with its label, such as dormir (ue). Many textbooks and learner word lists mark the change in brackets.
Do stem-changing verbs change in every tense?
No. This deck covers the present tense only. Other tenses follow their own rules, which you'll meet at A2.
Try it
Say each form out loud before you flip the card. Then order like you did in Bogotá: ¿Cómo se dice "We want two coffees, and I can't sleep after coffee"?