The e→i stem change is the smallest of the four stem-change families, and the most narrowly scoped: it occurs only in -ir verbs, and the change is a simple shift (not a diphthongization). A stressed e in the stem just slides to i: pedir → pido, servir → sirvo, repetir → repito. The boot pattern still applies — nosotros and vosotros sit outside it, keeping the simple e (pedimos, pedís).
This page covers the full -ir-only family, the spelling quirks of seguir and reír, and the trap of confusing e→i verbs with their e→ie cousins.
The mechanism: stressed e → i (shift, not diphthong)
Unlike e→ie and o→ue, the e→i pattern doesn't produce a diphthong — the stressed e simply raises to i. Compare:
- pensar (e→ie): pienso, piensas, piensa — diphthong.
- preferir (e→ie): prefiero, prefieres, prefiere — diphthong.
- pedir (e→i): pido, pides, pide — single vowel.
Why the difference? Historically, e→i comes from a different Latin vowel than e→ie. Spanish keeps the inherited distinction. Practically, it means you can't tell from a verb's infinitive whether it will go e→ie or e→i — you have to learn each verb individually.
A useful heuristic: e→i is exclusive to -ir verbs. No -ar or -er verb in Spanish takes this pattern. So the moment you see a non--ir infinitive with stem e, you can rule e→i out — it will be either e→ie or fully regular.
Pedir — full paradigm
The textbook model is pedir ("to ask for, to order"). Drop the -ir, and the stem is ped- in unstressed positions, pid- in stressed positions.
| Subject | Form | Stem |
|---|---|---|
| yo | pido | pid- (stressed → i) |
| tú | pides | pid- (stressed → i) |
| él / ella / usted | pide | pid- (stressed → i) |
| nosotros / nosotras | pedimos | ped- (unstressed, no change) |
| vosotros / vosotras | pedís | ped- (unstressed, no change) |
| ellos / ellas / ustedes | piden | pid- (stressed → i) |
Siempre pido un café solo.
I always order a black espresso.
¿Qué pedís para comer?
What are you guys getting to eat?
Los niños piden helado cada vez que pasamos por aquí.
The kids ask for ice cream every time we pass by here.
Servir, repetir, vestir — same pattern
These three verbs follow pedir exactly. The stem-vowel shifts from e to i in the boot, stays as e in nosotros and vosotros.
| Subject | servir | repetir | vestir |
|---|---|---|---|
| yo | sirvo | repito | visto |
| tú | sirves | repites | vistes |
| él / ella / usted | sirve | repite | viste |
| nosotros | servimos | repetimos | vestimos |
| vosotros | servís | repetís | vestís |
| ellos / ellas / ustedes | sirven | repiten | visten |
En este bar sirven unas tapas riquísimas.
They serve some incredible tapas at this bar.
¿Me lo repites, por favor? No te he oído bien.
Can you say that again, please? I didn't quite hear you.
Me visto en cinco minutos y bajo.
I'll get dressed in five minutes and come down.
Seguir and conseguir — the gu/g spelling change
The verb seguir ("to follow, to continue") is e→i like the others, but it adds a spelling complication. The infinitive carries a silent u (after g, the u is needed to keep the /g/ sound before e or i: seguir is pronounced /se.ɣir/, with hard g).
When the stem ends up before o or a (as in yo sigo or any subjunctive form), the u becomes unnecessary — and would, in fact, mislead the reader by suggesting a /gw/ sound. So the u drops.
| Subject | Form | Why |
|---|---|---|
| yo | sigo | e→i; gu→g before -o (no need to preserve hard g) |
| tú | sigues | e→i; gu kept before -e (otherwise it'd be /ʝe/) |
| él / ella / usted | sigue | e→i; gu kept |
| nosotros | seguimos | no stem change; gu kept |
| vosotros | seguís | no stem change; gu kept (ending starts with -í, needs the u to stay /g/) |
| ellos / ellas / ustedes | siguen | e→i; gu kept |
So the yo form is sigo, but the vosotros form is seguís — both correctly spelled, both pronounced with a hard /g/. This is purely an orthographic adjustment to keep the consonant sound consistent; the pronunciation rule is invariant.
Sigo trabajando aquí, pero estoy buscando algo mejor.
I'm still working here, but I'm looking for something better.
¿Vosotros seguís en contacto con ellos?
Are you guys still in touch with them?
Si seguimos así, llegamos tarde.
If we keep going like this, we'll be late.
The verb conseguir ("to manage to, to get") follows the same pattern: consigo, consigues, consigue, conseguimos, conseguís, consiguen. So does perseguir ("to pursue").
Reír and freír — the accent surprise
The verbs reír ("to laugh") and freír ("to fry") are e→i stem-changers, but with an extra wrinkle: an accent mark on the í in several forms, because the í and the ending vowel would otherwise form a diphthong that they shouldn't.
| Subject | reír | freír |
|---|---|---|
| yo | río | frío |
| tú | ríes | fríes |
| él / ella / usted | ríe | fríe |
| nosotros | reímos | freímos |
| vosotros | reís | freís |
| ellos / ellas / ustedes | ríen | fríen |
The accent on río, ríes, ríe, ríen breaks what would otherwise be a falling diphthong: without it, rio would be read as one syllable (/rjo/), not two (/ri.o/). The vosotros reís keeps an accent for the same reason — reís is two syllables (re-ís), and without the accent, the orthography wouldn't reflect that.
This is the same logic that gives us país (pa-ís, two syllables, accent on the í) and oído (o-í-do, accent on the í to break the diphthong).
Me río un montón cuando estoy con ellos.
I laugh a lot when I'm with them.
¿De qué os reís?
What are you guys laughing at?
Frío las patatas en aceite de oliva.
I fry the potatoes in olive oil.
The verb sonreír ("to smile") works the same way: sonrío, sonríes, sonríe, sonreímos, sonreís, sonríen.
A working list of e→i verbs
These are the everyday -ir verbs that follow this pattern.
| Verb | Meaning | Yo form |
|---|---|---|
| pedir | to ask for, to order | pido |
| servir | to serve | sirvo |
| repetir | to repeat | repito |
| seguir | to follow, to continue | sigo |
| conseguir | to manage to, to get | consigo |
| perseguir | to pursue | persigo |
| vestir(se) | to dress, to get dressed | (me) visto |
| despedir(se) | to dismiss, to say goodbye | (me) despido |
| medir | to measure | mido |
| reír(se) | to laugh | (me) río |
| sonreír | to smile | sonrío |
| freír | to fry | frío |
| elegir | to choose | elijo (g→j before o, similar to seguir's gu→g) |
| corregir | to correct | corrijo |
| impedir | to prevent | impido |
A spelling note on elegir and corregir: when the stem ends in g and the ending starts with o or a (as in yo elegir → elijo), the g changes to j to preserve the /x/ sound (the soft "h"-like Spanish g). Otherwise the g would be read as a hard /g/. This is the inverse of the seguir situation: there we drop a u; here we change g to j. Both moves serve the same goal: keep the consonant sound consistent.
Elijo el café con leche, por favor.
I'll go with the coffee with milk, please.
Mido un metro ochenta.
I'm one meter eighty (tall).
Sonrío cada vez que te veo.
I smile every time I see you.
Why -ir verbs are special
E→i is exclusive to -ir verbs because of how the -ir conjugation evolved from Latin. -ar and -er verbs inherited the diphthongization pattern (e→ie) cleanly, but in -ir verbs, the historical e sometimes raised to i under the influence of the -i- sound of the ending. Modern Spanish kept both outcomes: some -ir verbs went e→ie (preferir, sentir), others went e→i (pedir, servir). You can't predict from the infinitive which group a verb belongs to.
This also explains why -ir e→i verbs extend their change into the preterite (3rd persons: pidió, pidieron) and the gerund (pidiendo) — the same -i- influence keeps showing up. We'll cover this in stem changes in the preterite.
How English speakers go wrong
Two specific traps for English speakers:
- Confusing e→i with e→ie. Both are stem changes affecting verbs with e in the stem. The mistake of saying prifero (treating preferir as e→i) instead of prefiero (e→ie) is one of the most common — and the reverse, saying piedo instead of pido, is just as common. There is no shortcut: you have to memorize which verbs go which way. Pedir, servir, repetir are e→i. Preferir, sentir, mentir are e→ie.
- Forgetting the boot. The pull to say pidemos, pidéis — applying the change everywhere — is strong. But just like all stem changers, the change only applies where the stem is stressed.
Yo pido, tú pides, ella pide — pero nosotros pedimos y vosotros pedís.
Useful drill: the e→i family follows the boot just like the other stem-changers.
Some common collocations
- pedir + thing — to order, to ask for: pedir un café, pedir el menú.
- pedir + que + subjunctive — to ask someone to do something: Te pido que vengas.
- pedir disculpas / perdón — to apologize.
- servir para + thing/infinitive — to be useful for: Esto no sirve para nada.
- seguir + gerund — to keep doing something: Sigo trabajando ("I'm still working").
- conseguir + infinitive — to manage to do: Conseguí terminarlo ("I managed to finish it"). Note that this construction takes the indicative when describing what one actually accomplishes.
Te pido perdón por lo de ayer.
I'm sorry about yesterday. (lit. I ask you forgiveness for yesterday's thing)
Esto no sirve para nada.
This is useless. (lit. This is good for nothing)
Common mistakes
❌ Nosotros pidemos siempre lo mismo.
Wrong: nosotros is outside the boot. The form is pedimos.
✅ Nosotros pedimos siempre lo mismo.
Correct: pedimos.
❌ Vosotros pidéis demasiado vino.
Wrong: vosotros is outside the boot. The form is pedís — no shift.
✅ Vosotros pedís demasiado vino.
Correct: pedís, plain e.
This is the cardinal peninsular error in this family — the vosotros form keeps the e, not the shifted i.
❌ Yo prifero el té al café.
Wrong: preferir is e→ie, not e→i. The form is prefiero.
✅ Yo prefiero el té al café.
Correct: prefiero.
❌ Yo seguo trabajando aquí.
Wrong: the spelling change gu→g applies before -o. The form is sigo.
✅ Yo sigo trabajando aquí.
Correct: sigo.
❌ Yo rio mucho con esa película.
Wrong: río needs an accent to mark the hiatus between i and o.
✅ Yo río mucho con esa película.
Correct: río with accent.
❌ ¿De qué os reéis?
Wrong: the vosotros form is reís, not reéis.
✅ ¿De qué os reís?
Correct: reís.
Key takeaways
- The e→i pattern is exclusive to -ir verbs. No -ar or -er verb takes this change.
- It's a vowel shift, not a diphthongization: pido, not piedo.
- The change appears in the four boot forms (yo, tú, él, ellos) and not in nosotros or vosotros: pedimos, pedís.
- Seguir and conseguir combine e→i with a gu→g spelling change before o: sigo, consigo.
- Elegir and corregir combine e→i with a g→j spelling change before o: elijo, corrijo.
- Reír, freír, sonreír add accent marks to break what would otherwise be diphthongs: río, frío, sonrío — and vosotros reís, freís, sonreís.
- These -ir verbs extend the change into the 3rd-person preterite and gerund: pidió, pidiendo, sirvió, sirviendo.
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Start learning Spanish→Related Topics
- Cambios vocálicos en la raízA2 — The four stem-change patterns in Spanish verbs — e→ie, o→ue, e→i, u→ue — the 'boot' shape they make, and why vosotros sits outside the boot.
- pedirA1 — Full conjugation reference for pedir — an e→i stem-changing -ir verb (pido, pides, pide). Covers the third-person preterite (pidió, pidieron), the gerund (pidiendo), the present subjunctive (pida throughout), and the crucial pedir/preguntar distinction (request vs ask a question) that trips up English speakers.
- seguirA1 — Full conjugation reference for seguir (to follow, to continue, to still be doing something) — an e→i stem-changing -ir verb with the obligatory gu→g spelling change before a or o (sigo, siga, siguió, siguieron, siguiendo). Covers every tense, the seguir + gerund construction that maps to English 'still be doing,' and the common preposition confusions English speakers make.