Here is the most important fact about the irregular imperfect subjunctive in Spanish: there are no irregular imperfect subjunctives at the level of the imperfect subjunctive itself. Every form — fuera, tuviera, dijera, quisiera, hubiera — is built mechanically from the verb's third-person plural preterite. If a verb has an irregular preterite, the irregularity simply carries over. There is no second set of irregular stems to memorize. Master the preterite irregulars, and the imperfect subjunctive falls into your lap.
The rule, restated for irregular verbs
- Conjugate the verb in the third-person plural preterite.
- Drop the final -ron.
- Add the -ra endings (-ra, -ras, -ra, -ramos, -rais, -ran) or the -se endings (-se, -ses, -se, -semos, -seis, -sen).
- Add a written accent to the nosotros form.
That's it. Every "irregular" imperfect subjunctive is just the preterite irregularity wearing a subjunctive ending.
The major irregular families
Spanish irregular preterites fall into recognizable families. Let's walk through them with the imperfect subjunctive forms attached.
U-stem preterites
Verbs whose preterite stem switches to -u-: tener, estar, poder, poner, saber, haber, andar, caber. The preterite endings are unstressed (-e, -iste, -o, -imos, -isteis, -ieron), so the -ieron drop yields the imperfect subjunctive stem.
| Infinitive | 3pl preterite | Imperfect subjunctive (-ra) | Imperfect subjunctive (-se) |
|---|---|---|---|
| tener | tuvieron | tuviera, tuvieras, tuviera, tuviéramos, tuvierais, tuvieran | tuviese, tuvieses, tuviese, tuviésemos, tuvieseis, tuviesen |
| estar | estuvieron | estuviera... estuviéramos... estuvieran | estuviese... estuviésemos... estuviesen |
| poder | pudieron | pudiera... pudiéramos... pudieran | pudiese... pudiésemos... pudiesen |
| poner | pusieron | pusiera... pusiéramos... pusieran | pusiese... pusiésemos... pusiesen |
| saber | supieron | supiera... supiéramos... supieran | supiese... supiésemos... supiesen |
| haber | hubieron | hubiera... hubiéramos... hubieran | hubiese... hubiésemos... hubiesen |
| andar | anduvieron | anduviera... anduviéramos... anduvieran | anduviese... anduviésemos... anduviesen |
| caber | cupieron | cupiera... cupiéramos... cupieran | cupiese... cupiésemos... cupiesen |
Si tuviera coche, te llevaría a la estación.
If I had a car, I'd drive you to the station.
Le pedí que pusiera la mesa antes de que llegaran los invitados.
I asked him to set the table before the guests arrived.
I-stem preterites
Verbs whose preterite stem switches to -i-: hacer, querer, venir. (Add decir with extra complications below.)
| Infinitive | 3pl preterite | Imperfect subjunctive (-ra) | Imperfect subjunctive (-se) |
|---|---|---|---|
| hacer | hicieron | hiciera, hicieras, hiciera, hiciéramos, hicierais, hicieran | hiciese... hiciésemos... hiciesen |
| querer | quisieron | quisiera... quisiéramos... quisieran | quisiese... quisiésemos... quisiesen |
| venir | vinieron | viniera... viniéramos... vinieran | viniese... viniésemos... viniesen |
Quisiera reservar una mesa para cuatro a las nueve.
I'd like to reserve a table for four at nine.
The -ra form quisiera is also a polite formula in service contexts — Quisiera un café sounds more polished than Quiero un café. The conditional querría exists too, but quisiera is more idiomatic in spoken Spain.
Esperaba que vinieras antes, pero entiendo que se te complicara el día.
I was hoping you'd come earlier, but I understand your day got complicated.
J-stem preterites (and the -eron rule)
A small but high-frequency group has a stem ending in -j-: decir, traer, and verbs in -ducir like conducir, traducir, producir. These verbs take -eron rather than -ieron in the third-person plural preterite — the -i- is absorbed by the -j-. The imperfect subjunctive inherits this: dijeran, not dijieran.
| Infinitive | 3pl preterite | Imperfect subjunctive (-ra) | Imperfect subjunctive (-se) |
|---|---|---|---|
| decir | dijeron | dijera, dijeras, dijera, dijéramos, dijerais, dijeran | dijese... dijésemos... dijesen |
| traer | trajeron | trajera... trajéramos... trajeran | trajese... trajésemos... trajesen |
| conducir | condujeron | condujera... condujéramos... condujeran | condujese... condujésemos... condujesen |
| traducir | tradujeron | tradujera... tradujéramos... tradujeran | tradujese... tradujésemos... tradujesen |
The accent on dijéramos is on the -jé- syllable (three from the end) — same proparoxytone rule as everywhere else.
Me molestó que dijeras eso delante de todos.
It bothered me that you said that in front of everyone.
No había nadie que tradujera tan bien del francés como ella.
There was no one who translated from French as well as she did.
Ser and ir: identical and irregular
The preterites of ser and ir are identical — fui, fuiste, fue, fuimos, fuisteis, fueron — and so are their imperfect subjunctives. Context tells you which one is meant.
| Person | -ra forms | -se forms |
|---|---|---|
| yo | fuera | fuese |
| tú | fueras | fueses |
| él / ella / usted | fuera | fuese |
| nosotros | fuéramos | fuésemos |
| vosotros | fuerais | fueseis |
| ellos / ellas / ustedes | fueran | fuesen |
Si fuera tú, no le contestaría todavía.
If I were you, I wouldn't reply to him yet.
Le dije que fuera al médico, pero no me hizo caso.
I told him to go to the doctor, but he didn't listen.
In the first example, fuera maps to ser (si fuera tú — if I were you). In the second, fuera maps to ir (que fuera al médico — that he go to the doctor). Native speakers process this disambiguation effortlessly; you will too, with practice.
Dar and the -er pattern
Dar is irregular in the preterite (it conjugates like an -er verb: di, diste, dio, dimos, disteis, dieron) and inherits this into the imperfect subjunctive: diera, dieras, diera, diéramos, dierais, dieran (or -se equivalents).
Quería que me diera su opinión, pero solo me dio largas.
I wanted him to give me his opinion, but he just stalled.
Verbs with a y in the preterite
-er and -ir verbs whose stem ends in a vowel (leer, oír, caer, construir, huir, creer) insert a -y- in the third-person preterite: leyeron, oyeron, cayeron, construyeron, huyeron, creyeron. This y stays in the imperfect subjunctive.
| Infinitive | 3pl preterite | Imperfect subjunctive (-ra) |
|---|---|---|
| leer | leyeron | leyera, leyeras, leyera, leyéramos, leyerais, leyeran |
| oír | oyeron | oyera, oyeras, oyera, oyéramos, oyerais, oyeran |
| caer | cayeron | cayera... cayéramos... cayeran |
| construir | construyeron | construyera... construyéramos... construyeran |
No me extrañó que oyera ruidos por la noche; la casa es muy vieja.
It didn't surprise me that she heard noises at night; the house is very old.
-ir verbs with an e → i or o → u shift in the preterite
Stem-changing -ir verbs (pedir, servir, dormir, morir, sentir, mentir, seguir, repetir) shift in the third-person preterite, and that shift carries over.
| Infinitive | 3pl preterite | Imperfect subjunctive (-ra) |
|---|---|---|
| pedir | pidieron | pidiera, pidieras, pidiera, pidiéramos, pidierais, pidieran |
| servir | sirvieron | sirviera... sirviéramos... sirvieran |
| dormir | durmieron | durmiera... durmiéramos... durmieran |
| morir | murieron | muriera... muriéramos... murieran |
| sentir | sintieron | sintiera... sintiéramos... sintieran |
Era extraño que durmiera tan poco a su edad.
It was strange that he slept so little for his age.
Le dije al camarero que nos sirviera vino de la casa.
I told the waiter to serve us house wine.
Putting it together: vosotros in peninsular Spanish
Every irregular imperfect subjunctive has a peninsular vosotros form. The accent rule is the usual one — paroxytone in -s, no written accent — so all of these are unaccented in spelling:
| Verb | -ra vosotros | -se vosotros |
|---|---|---|
| ser / ir | fuerais | fueseis |
| tener | tuvierais | tuvieseis |
| poder | pudierais | pudieseis |
| hacer | hicierais | hicieseis |
| decir | dijerais | dijeseis |
| haber | hubierais | hubieseis |
Si vosotros tuvierais que elegir, ¿qué haríais?
If you (all) had to choose, what would you do?
Os pedí que fueseis discretos y, sin embargo, lo contasteis todo.
I asked you (all) to be discreet, and yet you told everyone.
What English does instead
English handles all of these with a flat past indicative or a "would"/"could" modal:
- If I had it → Si lo tuviera
- I wished you'd told me → Ojalá me lo hubieras dicho (pluperfect subjunctive — same stem family)
- She wanted me to go → Quería que fuera
- We asked him to bring it → Le pedimos que lo trajera
Notice how varied the English is — past indicative, "would" + past participle, infinitive complement — and how the Spanish reduces all of it to a single morphological category: imperfect subjunctive built from the preterite stem.
Common mistakes
❌ Si tendría tiempo, iría.
Incorrect — conditional in the si-clause.
✅ Si tuviera tiempo, iría.
If I had time, I'd go.
The cardinal English-speaker error. The si-clause never takes the conditional in a counterfactual; tuviera (or tuviese) is required.
❌ Me pidió que digiera la verdad.
Incorrect — invented form *digiera.
✅ Me pidió que dijera la verdad.
He asked me to tell the truth.
The stem of decir in the imperfect subjunctive is dij- (from dijeron), not digi-. The g/j spelling change from the present subjunctive (diga) does not apply here.
❌ Quería que estaran allí.
Incorrect — *estaran is not a Spanish form.
✅ Quería que estuvieran allí.
I wanted them to be there.
The preterite of estar is estuvieron, so the imperfect subjunctive stem is estuvie-, not esta-. Always derive from the preterite.
❌ Si saberías lo que pasó, llamarías a la policía.
Incorrect — *saberías is not a Spanish form, and the conditional is wrong in the si-clause anyway.
✅ Si supieras lo que pasó, llamarías a la policía.
If you knew what happened, you'd call the police.
Saber has the irregular preterite supieron, so the imperfect subjunctive is supiera/supiese, not anything built off the present stem.
❌ Pasamos miedo cuando creían que no llegáramos.
Mixed-up tense logic — clause needs adjustment.
✅ Pasamos miedo cuando creyeron que no llegaríamos.
We were scared when they thought we wouldn't get there.
Creer que with an indicative meaning takes indicative, not subjunctive. Don't reach for the imperfect subjunctive just because everything else in the sentence is past — the trigger has to actually require the subjunctive.
Key takeaways
- Every irregular imperfect subjunctive is built from the 3rd-plural preterite. No extra stems to learn.
- The j-stem verbs (decir, traer, conducir) drop the i of -ieron → -eron, and that e carries into the subjunctive (dijera, not dijiera).
- Ser and ir share an identical paradigm: fuera, fuese, fueras, fueses… — context disambiguates.
- The vosotros forms never carry a written accent (tuvierais, pudieseis).
- The nosotros forms always do (tuviéramos, pudiésemos).
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Start learning Spanish→Related Topics
- Imperfecto de subjuntivo en -raB2 — Build the -ra forms of the imperfect subjunctive from the preterite stem and use them in past triggers, counterfactual si-clauses, and ojalá-wishes.
- Imperfecto de subjuntivo en -seB2 — The -se imperfect subjunctive is a fully alive, fully correct alternative to the -ra form in peninsular Spanish — formation, accents, and how it differs in feel.
- Disparadores en pasado: imperfecto de subjuntivoB2 — When the main clause is past-tense or conditional, subjunctive triggers force the subordinate verb back into the imperfect subjunctive — the sequence-of-tenses rule that drives most uses of -ra and -se.
- Pretérito con raíz en -u-: estar, tener, poder, poner, saberB1 — The strong-preterite family whose stem warps to -u-: estuve, tuve, pude, puse, supe — sharing one set of unaccented endings and producing several of the highest-frequency verbs in spoken Spanish.
- Pretérito con raíz en -i-: hacer, querer, venirB1 — The three highest-frequency irregular preterites that rebuild their stem around -i-: hice, quise, vine. Same unstressed endings as the u-stem family, plus a spelling twist in hizo and meaning shifts in quise.