Lesson 37: Imperfecto de subjuntivo — forms

Part 1: "If I were you" — the English fossil

English speakers, listen up. You already have the imperfect subjunctive — you just don't know it. When you say "If I were you" (not "if I was you"), "I wish I knew", "It's time we left" — that were / knew / left is the English fossil of exactly this tense. It's a leftover from when English actually had a subjunctive mood.

The catch: in English it's almost dead — only a few set phrases survive. In Spanish it's alive and constant. The moment your main clause goes into the past or the conditional, this is the form you reach for.

Si yo fuera tú — "If I were you". Same logic, same form, same mood. Spanish just kept the system intact.

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Part 2: Why we need a past subjunctive

In Lessons 31–36 you mastered the presente de subjuntivo: quiero que vengas, no creo que sea verdad, cuando llegues, llámame.

But the moment the trigger verb moves into the past or the conditional, the present subjunctive is no longer enough. You need its past sibling — the imperfecto de subjuntivo.

Present trigger → presente de subjuntivo	Past / conditional trigger → imperfecto de subjuntivo
Quiero que vengas. — I want you to come.	Quería que vinieras. — I wanted you to come.
Me alegro de que estés aquí. — I'm glad you're here.	Me alegré de que estuvieras aquí. — I was glad you were here.
No creo que sea verdad. — I don't think it's true.	No creía que fuera verdad. — I didn't think it was true.
Cuando llegues, llámame. — When you arrive, call me.	Me dijo que cuando llegara, lo llamara. — He told me to call him when I arrived.
Es importante que estudies. — It's important that you study.	Era importante que estudiaras. — It was important that you studied.

Sequence-of-tenses rule in one line: main clause in the past or conditional → subordinate clause in the imperfect subjunctive. Always. Don't try to use the present subjunctive here — it won't fly.

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Part 3: The master rule — preterite as base

Take the 3rd-person plural of the pretérito indefinido, drop -ron, add the endings.

In plain English: if you know the forms hablaron, comieron, vivieron, tuvieron, dijeron, fueron, supieron — you already have the stem. The imperfect subjunctive is not a new set of forms but a reprocessing of what you nailed down in Lessons 21–22.

Three-step algorithm:

1. Find the 3rd-pl. preterite:    hablaron
2. Drop the -ron ending:          habla-
3. Add the endings:               hablara, hablaras, hablara, habláramos, hablarais, hablaran

This works for every single verb — regular, irregular, stem-changing. Zero exceptions. That's why this lesson is mostly mechanical: master the preterite (which you already did) and the imperfect subjunctive falls out for free.

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Part 4: Two sets of endings — -ra and -se

Spanish offers two fully interchangeable sets of endings for the imperfect subjunctive. They mean the same thing, in any context.

The -RA set (dominant — Latin America and modern Spain, everyday speech)

Person	Ending	hablar	comer	vivir
yo	-ra	hablara	comiera	viviera
tú	-ras	hablaras	comieras	vivieras
él / ella / usted	-ra	hablara	comiera	viviera
nosotros	-´ramos (tilde!)	habláramos	comiéramos	viviéramos
vosotros	-rais	hablarais	comierais	vivierais
ellos / ustedes	-ran	hablaran	comieran	vivieran

Watch the tilde on the nosotros form! Habláramos, comiéramos, viviéramos. Without that tilde the stress slides forward and the word reads wrong. The tilde marks an esdrújula — stress on the third-from-last syllable. Don't skip it.

The -SE set (more formal, more bookish, more common in written Spain)

Person	Ending	hablar	comer	vivir
yo	-se	hablase	comiese	viviese
tú	-ses	hablases	comieses	vivieses
él / ella / usted	-se	hablase	comiese	viviese
nosotros	-´semos	hablásemos	comiésemos	viviésemos
vosotros	-seis	hablaseis	comieseis	vivieseis
ellos / ustedes	-sen	hablasen	comiesen	viviesen

Practical recommendation: actively learn the -ra forms. Recognize the -se forms in books, newspapers, legal documents, and formal speech. When you speak, use -ra and you'll be understood everywhere. Choose one and stick with it inside a single sentence — don't mix.

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Part 5: Drill — irregular preterites become imperfect subjunctive

This is the heart of the lesson. We take the "ugly" preterites from L22 and run the mechanism on each. Listen carefully: the base of the imperfect subjunctive is NOT the infinitive — it's the 3rd-person plural of the preterite.

Infinitive	3rd-pl. preterite	Stem	Imperf. subj. (yo, -ra)	-se alternative
tener	tuvieron	tuvie-	tuviera	tuviese
estar	estuvieron	estuvie-	estuviera	estuviese
poder	pudieron	pudie-	pudiera	pudiese
poner	pusieron	pusie-	pusiera	pusiese
saber	supieron	supie-	supiera	supiese
hacer	hicieron	hicie-	hiciera	hiciese
venir	vinieron	vinie-	viniera	viniese
querer	quisieron	quisie-	quisiera	quisiese
decir	dijeron	dije-	dijera	dijese
traer	trajeron	traje-	trajera	trajese
ser	fueron	fue-	fuera	fuese
ir	fueron	fue-	fuera	fuese
dar	dieron	die-	diera	diese
ver	vieron	vie-	viera	viese
pedir	pidieron	pidie-	pidiera	pidiese
dormir	durmieron	durmie-	durmiera	durmiese
sentir	sintieron	sintie-	sintiera	sintiese
leer	leyeron	leye-	leyera	leyese
oír	oyeron	oye-	oyera	oyese
construir	construyeron	construye-	construyera	construyese
haber	hubieron	hubie-	hubiera	hubiese

Notice: ser and ir are identical in the imperfect subjunctive — both give fuera / fuese. You tell them apart only from context: Quería que fuera médico = "I wanted him to be a doctor" (ser) or "I wanted him to go to/become a doctor" (ir). In practice, confusion almost never comes up.

Dar gives diera / diese — no tilde, no doubled vowel; the stem is die- (from dieron), not di-.

Verbs whose preterite stem ends in -j- (decir → dijeron, traer → trajeron, conducir → condujeron) drop the i of -ieron in the preterite. Same in the subjunctive: dijera, trajera, condujera — not dijiera.

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Part 6: When to use it — past and conditional triggers

The imperfect subjunctive shows up in exactly the same slots as the present subjunctive (WEIRDO — Wishes, Emotions, Impersonal expressions, Recommendations, Doubt/denial, Ojalá), but only when the main verb is in the past (preterite, imperfect, pluperfect) or in the conditional.

Trigger type	Present (you know this)	Past / conditional (new)
Will / command	Quiero que vengas.	Quería que vinieras. — I wanted you to come.
	Te pido que me ayudes.	Te pedí que me ayudaras. — I asked you to help me.
	Le digo que estudie.	Le dije que estudiara. — I told him to study.
Emotion / judgment	Me alegro de que estés aquí.	Me alegré de que estuvieras aquí. — I was glad you were here.
	Es bueno que vengas.	Era bueno que vinieras. — It was good that you came.
	Tengo miedo de que pase algo.	Tenía miedo de que pasara algo. — I was afraid something would happen.
Doubt / negation	No creo que sea verdad.	No creía que fuera verdad. — I didn't think it was true.
	Dudo que tenga razón.	Dudaba que tuviera razón. — I doubted he was right.
Adjective / adverbial	Busco a alguien que hable ruso.	Buscaba a alguien que hablara ruso. — I was looking for someone who spoke Russian.
	Aunque sea difícil, lo haré.	Aunque fuera difícil, lo haría. — Even if it were difficult, I'd do it.
Conditional main clause	—	Sería bueno que estudiaras. — It would be good if you studied.
	—	Me gustaría que vinieras. — I'd like you to come.

One-line rule: Quiero que vengas (present + present subj.) → Quería que vinieras (past + imperfect subj.). Match the times and you can't go wrong.

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