Spanish conditional ("si") sentences come in three types, depending on how real or how far in the past the condition is.
| Type | Si clause | Main clause |
|---|---|---|
| 1. Real / likely | present indicative | present / future / imperative |
| 2. Hypothetical | imperfect subjunctive | conditional |
| 3. Contrary-to-fact (past) | pluperfect subjunctive | conditional perfect |
Imperfect subjunctive: take the ellos preterite, drop -ron, add -ra/-ras/-ra/-ramos/-rais/-ran. Hablaron → hablara.
Conditional: infinitive + -ía/-ías/-ía/-íamos/-íais/-ían. Viajar → viajaría.
Conditional perfect: habría + participle. Habría llamado.
The rule that trips up every learner: after si you can never use the present subjunctive or the conditional. Si tendría ✗ and si tenga ✗ are both wrong. It's si tengo or si tuviera. This is the single most recognisable advanced-learner error.
Type 3 shortcut: both clauses can use the pluperfect subjunctive interchangeably — Si hubiera sabido, te hubiera llamado works just as well as habría llamado. You'll hear both in real speech.
The two halves don't have to share a time frame. A past condition can have a present consequence, which is where regret really lives.
| Structure | Nuance | Example |
|---|---|---|
| de + infinitivo | compact, formal | De haberlo sabido, te habría llamado. |
| como + subjuntivo | warning or threat | Como llegues tarde, me voy. |
| siempre que / con tal de que | provided that | Te ayudo siempre que me lo pidas. |
| en caso de que | in case | En caso de que llueva, llévate el paraguas. |
| a no ser que / a menos que | unless | Iré a menos que llueva. |
All of these take the subjunctive — except si. That's the quirk: si is the one conditional connector that uses the indicative in type 1. Every alternative in the table above requires a subjunctive.
1.Si ___ (tener, yo) tiempo, voy al gimnasio.
2.Si ___ (ser, yo) rico, compraría una casa en la playa.
3.Si ___ (estudiar, yo) más, habría aprobado.
4.Si practicaras cada día, ___ (aprender, tú) mucho más rápido.
5.Si no hubiéramos salido tan tarde, no ___ (perder, nosotros) el tren.
6.Which is WRONG in Spanish?
7.Si ___ (poder, yo) ayudarte, lo haría encantado.
8.Si hubiera estudiado medicina, ahora ___ (ser, yo) médico.
9.Como ___ (llegar, tú) tarde otra vez, me voy sin ti.
10.Te ayudo siempre que me lo ___ (pedir, tú) con tiempo.
11.Which structure means the same as "Si lo hubiera sabido"?
12.Iré a la fiesta a menos que ___ (llover).
Book a class with Ángel and talk through regrets and hypotheses — nothing drills conditionals like discussing what you'd have done differently.