Here is the good news: the imperfect subjunctive has no irregular endings of its own. Every irregularity comes directly from the third person plural preterite. If you already know the irregular preterites, the imperfect subjunctive is essentially free.
The Rule, One More Time
Take the ellos/ellas/ustedes preterite, drop -ron, add the subjunctive endings. Because strong preterites have unusual stems, those stems simply carry over into the imperfect subjunctive.
tener → tuvieron → tuviera
to have → they had → (that) I had
hacer → hicieron → hiciera
to do → they did → (that) I did
Common Irregular Verbs
| Infinitive | 3rd Plural Preterite | Imperfect Subjunctive (yo) |
|---|---|---|
| tener | tuvieron | tuviera |
| hacer | hicieron | hiciera |
| decir | dijeron | dijera |
| ser / ir | fueron | fuera |
| estar | estuvieron | estuviera |
| poder | pudieron | pudiera |
| poner | pusieron | pusiera |
| querer | quisieron | quisiera |
| saber | supieron | supiera |
| venir | vinieron | viniera |
| dar | dieron | diera |
| ver | vieron | viera |
Tener (full conjugation)
Third person plural preterite: tuvieron. Stem: tuvie-.
| Subject | Form |
|---|---|
| yo | tuviera |
| tú | tuvieras |
| él / ella / usted | tuviera |
| nosotros | tuviéramos |
| ellos / ellas / ustedes | tuvieran |
Ser / Ir (full conjugation)
Ser and ir share the same preterite, fueron, so they share the same imperfect subjunctive too. Context is the only thing that distinguishes them.
| Subject | Form |
|---|---|
| yo | fuera |
| tú | fueras |
| él / ella / usted | fuera |
| nosotros | fuéramos |
| ellos / ellas / ustedes | fueran |
Si yo fuera tú, no iría.
If I were you, I wouldn't go.
Nos pidió que fuéramos al mercado.
She asked us to go to the market.
Decir — The J-Stem
Verbs whose preterite stem ends in j (dijeron, trajeron, condujeron) drop the i from the ending. Instead of dijieron, you get dijeron. That same short stem carries into the subjunctive.
| Subject | Form |
|---|---|
| yo | dijera |
| tú | dijeras |
| él / ella / usted | dijera |
| nosotros | dijéramos |
| ellos / ellas / ustedes | dijeran |
Le pedí que me dijera la verdad.
I asked him to tell me the truth.
Stem-Changing -Ir Verbs
Verbs like pedir, sentir, dormir, and morir change their stem vowel in the third person plural preterite, and that change carries over.
Esperaba que durmieras bien.
I was hoping you slept well.
No creí que pidieran ayuda.
I didn't think they would ask for help.
Continue to -ra vs -se forms or past-tense triggers.
Related Topics
- Imperfect Subjunctive: -Ra FormsB2 — Learn how to form the imperfect subjunctive using the -ra endings, the most common form in Latin American Spanish.
- Imperfect Subjunctive: -Se FormsB2 — Learn the alternative -se endings of the imperfect subjunctive, more common in literary and peninsular Spanish.
- Past-Tense TriggersB2 — How the imperfect subjunctive pairs with past-tense main clauses to maintain sequence of tenses.