Present tense: stem-changing verbs (e → ie, o → ue, e → i, u → ue)

What it is

Some of the most common Spanish verbs change the vowel of their stem when that vowel is stressed: querer → quiero, poder → puedo, pedir → pido, jugar → juego. The endings are the regular present-tense endings; only the stem changes. It changes in the yo, tú, él/ella/usted and ellos/ellas/ustedes forms, where the stress falls on the stem. In nosotros the stress moves to the ending, so the stem stays as in the infinitive: queremos, podemos, pedimos, jugamos. Draw a line around the changed forms in a full table and you get the shape of a boot, which is why they are often called "boot verbs".

How to form it

The four groups, with the verbs to learn first:

• e → ie: querer, pensar, empezar, cerrar, entender, preferir. You already know one: tener (tienes, tiene, tienen).
• o → ue: poder, volver, dormir, encontrar, costar, recordar.
• e → i, only in -ir verbs: pedir, repetir, servir, seguir (sigo, sigues).
• u → ue: only jugar.

The infinitive doesn't show the change, so learn each verb with its yo form: pensar (pienso), volver (vuelvo), pedir (pido). Spelling stays regular: empieza keeps its z, and sigue keeps the u that makes the g hard.

In Spain, vosotros keeps the stem too (queréis, podéis), and so does vos in Argentina and Uruguay: vos querés, podés, pedís, jugás.

When to use it

These verbs run daily life: wanting and preferring, being able to, starting and closing, ordering food, asking prices.

• Quiero un jugo de mango, por favor.I'd like a mango juice, please.querer: e → ie
• La clase empieza a las nueve.The class starts at nine.empezar: e → ie
• ¿Puedes repetir, por favor? No entiendo.Can you repeat that, please? I don't understand.poder, repetir, entender
• ¿Cuánto cuestan las naranjas?How much are the oranges?costar agrees with the thing
• En Caracas siempre pido arepas.In Caracas I always order arepas.pedir: e → i
• Los sábados jugamos al fútbol.On Saturdays we play football.nosotros: no change

• costar agrees with what is sold: El libro cuesta diez dólares. Los libros cuestan veinte.
• jugar + game or sport: jugar al fútbol (Spain, Argentina, Chile…) or jugar fútbol (Mexico, Central America, Colombia…). Both are correct. Instruments take tocar: toco la guitarra.
• pedir is to ask for something (pido la cuenta); preguntar, a regular verb, is to ask a question (pregunto la hora).

Contrasts and traps

• Nosotros never changes: podemos, not puedemos; queremos, not quieremos.
• e → i or e → ie? Only -ir verbs have e → i, but not every -ir verb: pedir → pido, but preferir → prefiero.
• juego or jugo? Juego is "I play"; jugo is "juice".
• Not every verb changes: comer, comprar, aprender, tomar are regular (como, compro, aprendo). Learn the changers as a list.

If you also speak Portuguese

Portuguese doesn't split these vowels, so the Portuguese form slips in: quero → quiero, posso → puedo, durmo → duermo, jogo → juego, peço → pido, custa → cuesta. In nosotros the two languages agree: queremos, podemos.