What if: conditionals and hypotheticals

To talk about a situation that is not true now, or is unlikely, Spanish pairs two tenses:

• the if clause: si + imperfect subjunctive (tuviera, fuera, pudiera)

• the result: conditional (visitaría, comería, sería)

Si tuviera coche, visitaría a mis padres más a menudo. — If I had a car, I would visit my parents more often. (I don't have one.)

The imperfect subjunctive comes from the ellos preterite: tuvieron → tuviera, fueron → fuera, pudieron → pudiera. There is also an -se form (tuviese), common in Spain and in writing, and correct everywhere.

The English-speaker trap is matching English word for word. English "had" in "if I had" looks past, but it means now, so it is not si tenía. And never put the conditional after si: si tendría is a classic mistake. The conditional belongs only in the result.

The order can flip without changing the tenses: visitaría a mis padres si tuviera coche.

How to decide: if the condition is imaginary or contrary to fact right now, use si + -ra form, and -ría in the other half.

"Would have done" is the conditional perfect: habría, habrías, habría, habríamos, habrían + past participle.

• Yo no habría dicho eso. — I wouldn't have said that.

• A tu abuela le habría encantado. — Your grandmother would have loved it.

You do not always need an if-clause. Spanish uses it on its own for advice about the past (yo en tu lugar habría llamado), for what almost happened (sin el mapa, nos habríamos perdido), and for imagining reactions (se habría reído).

The English-speaker trap is the conditional alone: yo no diría eso means "I wouldn't say that", about now or in general. If English has "would have", Spanish needs habría + participle. Watch the participle too: irregular ones like dicho, hecho, visto, puesto, vuelto and escrito are where most mistakes happen.

You will also hear natives use hubiera + participle with the same meaning: yo no hubiera dicho eso. It is very common in speech on both sides of the Atlantic and perfectly correct. Either form is fine; just do not mix in the simple conditional.

To imagine a different past, one that did not happen, Spanish pairs:

• the if clause: si + pluperfect subjunctive (hubiera + participle)

• the result: conditional perfect (habría + participle)

Si me hubieras llamado, te habría recogido en el aeropuerto. — If you had called me, I would have picked you up at the airport. (You didn't call.)

Hubiera comes in all persons: hubiera, hubieras, hubiera, hubiéramos, hubieran (and hubierais for vosotros in Spain). The -se forms (hubiese) are equally correct.

The English-speaker trap is the English pluperfect "had called". It tempts learners to write si me habías llamado, which is the indicative and sounds like a real fact. After si, an unreal past needs hubiera. And never si habría: the conditional stays in the result.

In the result, natives often use hubiera instead of habría: si me hubieras llamado, te hubiera recogido. Both are correct. What matters is that both halves point to the past.

How to decide: if English says "if … had done, … would have done", and it's about something that did not happen, it's hubiera + habría (or hubiera twice).

Real life does not always stay in one time frame, and Spanish tenses follow the meaning of each half, not a fixed formula.

• Real condition: si + indicative. Si ves a Carlos mañana, dile que lo llamo. No subjunctive at all.

• Past cause, present result: si hubiera estudiado medicina, ahora sería médico. Pluperfect subjunctive, then simple conditional.

• Present cause, past result: si fuera más cuidadosa, no habría perdido el pasaporte. Imperfect subjunctive (she is careless in general), then conditional perfect.

• As if: como si always takes the imperfect or pluperfect subjunctive. Me habla como si fuera un niño.

The English-speaker trap is to learn "si + subjunctive" as a rule and apply it everywhere. A real, possible future condition takes the present indicative: si llueve, never si llueva. And the present subjunctive never follows si in the if-sense.

How to decide: look at each half separately. Ask "is this condition possible or imaginary?" for the si clause, and "is this result about now or about the past?" for the other half. Then pick each tense on its own.

The pluperfect subjunctive (hubiera + participle) is not only for if-clauses. It is the tense for any wish or comparison about a past that did not happen.

• Regret: ojalá hubiera sacado más fotos (I wish I had taken more photos). After ojalá, the hubiera form means the chance is gone.

• If only: si me lo hubieras dicho antes… can stand alone as an exclamation.

• As if about the past: me saludó como si no hubiera pasado nada (she greeted me as if nothing had happened).

The English-speaker trap is "I wish". Deseo is not the word for regret, and ojalá + imperfect subjunctive (ojalá tuviera) is about now. To regret the past, it must be ojalá + hubiera. The other natural option is me hubiera gustado + infinitive (me hubiera gustado sacar más fotos), which uses the same tense.

Compare the tenses after como si: como si fuera un niño compares with something now; como si hubiera visto un fantasma compares with something that would have happened before.

How to decide: if English says "had done" and the event never took place, Spanish wants hubiera (or hubiese) + participle.

English has a formal shortcut for past conditions: "Had I known…" instead of "If I had known…". Spanish has one too, and it is used in speech as well as writing: de + haber + participle.

• De haberlo sabido, te habría avisado. — Had I known, I would have warned you.

• De haber salido antes, habríamos llegado a tiempo. — Had we left earlier, we would have arrived on time.

The infinitive does not show who did it, so context tells you the subject. Pronouns attach to haber: de haberlo sabido, de habérmelo dicho.

For "had it not been for…", use de no ser por: de no ser por ti, me habría perdido. In casual speech the result is often in the present for vividness: de no ser por ti, me pierdo.

The English-speaker trap is translating "had I known" with había, or turning it into a question. The de construction is the natural match; a full si lo hubiera sabido is also correct, just longer.

How to decide: when English inverts "had" to open a sentence, reach for de haber + participle, and finish with habría + participle.