La regla principal
Segundo condicional (presente o futuro irreal): if + past simple, would / could / might + verbo. Tercer condicional (pasado irreal): if + past perfect, would / could / might have + participio. El tiempo del que hablas decide el tipo, y would nunca va en la cláusula con if.
Formas
| Tipo | Cláusula con if | Oración principal | Ejemplo |
|---|---|---|---|
| segundo | if + past simple | would / could / might + verbo | If I had more time, I would learn Italian. |
| segundo, negativa | if + didn't + verbo | wouldn't + verbo | If she didn't work nights, she wouldn't be so tired. |
| segundo, pregunta | if + past simple | What would you do? / Would you ...? | What would you do if you won the lottery? |
| tercero | if + past perfect | would / could / might have + participio | If we had left earlier, we would have caught the train. |
| tercero, negativa | if + hadn't + participio | wouldn't have + participio | If he hadn't missed the bus, he wouldn't have been late. |
| tercero, pregunta | if + past perfect | What would you have done? / Would you have ...? | What would you have done if you had lost the key? |
Aquí el español ayuda: si + imperfecto de subjuntivo («Si tuviera tiempo, aprendería italiano») corresponde a if + past simple + would, y si + pluscuamperfecto de subjuntivo («Si hubiéramos salido antes, habríamos llegado») corresponde a if + past perfect + would have. La trampa está en el condicional «-ría»: como en español aparece en la oración principal de los dos tipos, es fácil ponerlo también tras si, y en inglés se acaba escribiendo would en la cláusula con if. No lo hagas: *If I would have time. Se dice If I had time, I would... Cuidado también con el segundo y el tercero: en español hay que cambiar el verbo («tuviera» frente a «hubiera tenido»), y en inglés hay que cambiar el tiempo, así que mira siempre si hablas del presente o del pasado. Contracciones: I'd puede ser I would o I had, y lo decide la palabra siguiente: I'd go es would, I'd gone es had.
Ejemplos
- If I had more time, I would learn Italian. Si tuviera más tiempo, aprendería italiano.
- If I were you, I would talk to your manager. Yo, en tu lugar, hablaría con tu jefe.
- What would you do if you won the lottery? ¿Qué harías si te tocara la lotería?
- She wouldn't be so tired if she didn't work nights. No estaría tan cansada si no trabajara por las noches.
- If we had left earlier, we would have caught the train. Si hubiéramos salido antes, habríamos tomado el tren.
- If he hadn't missed the bus, he wouldn't have been late. Si no hubiera perdido el autobús, no habría llegado tarde.
- I could have helped you if you had asked. Podría haberte ayudado si me lo hubieras pedido.
- If the weather had been better, we might have gone to the beach. Si hubiera hecho mejor tiempo, quizás habríamos ido a la playa.
- What would you have done if you had lost your passport? ¿Qué habrías hecho si hubieras perdido el pasaporte?
Segundo condicional: presente y futuro irreales
El segundo condicional describe lo que ahora no es real o es poco probable: If I had a car, I would drive to work (no tengo coche). También sirve para un futuro imaginado: If I won the lottery, I would buy a house. El verbo en la cláusula con if está en past simple, pero no indica pasado, sino irrealidad. Por eso con be se usa were con todas las personas: If I were taller, I could play basketball. En la conversación was también es normal (If I was taller), pero en la expresión fija If I were you solo va were.
Para aconsejar: If I were you
Para dar un consejo se dice If I were you, I would..., nuestro «yo, en tu lugar,...»: If I were you, I would apply for that job. Te pones en el lugar del otro, y el consejo suena más suave que una orden. Nunca *If I am you.
Tercer condicional: pasado irreal
El tercer condicional habla de un pasado que ya no se puede cambiar: algo ocurrió (o no) e imaginamos otro resultado. Esquema: if + past perfect, would have + participio: If I had known about the party, I would have come. (No lo sabía y no vine.) Suele expresar pesar, reproche o explicación: If you hadn't helped me, I would have failed. La negación va en las dos partes: hadn't y wouldn't have.
Would, could, might: tú eliges
En la oración principal el verbo modal cambia el sentido: would indica un resultado casi seguro, could una posibilidad o capacidad, might solo una probabilidad. If I had a day off, I would sleep (seguro). If I had a day off, I could visit you (podría). If I had a day off, I might go to the lake (quizás). En el tercer condicional pasa igual: would have, could have, might have.
Segundo o tercero: por el tiempo
Fíjate en el tiempo del que hablas. Now, these days, tomorrow, next year piden el segundo: If I knew the answer now, I would tell you. Yesterday, last year, in 2010 o un relato en pasado piden el tercero: If I had known the answer yesterday, I would have told you. Las dos partes de la oración se refieren siempre al mismo momento.
Segundo o primero: por la probabilidad
El primer condicional (B1) habla de una posibilidad real: If it rains tomorrow, we will stay at home (la lluvia es posible). El segundo habla de lo que el hablante no cree o no puede ser: If I were you, I would stay at home (yo no soy tú). Compara: If I win, I will buy a car (hay opción) y If I won, I would buy a car (lo veo improbable). A menudo es cuestión de cómo ve la situación quien habla, así que el contexto debe decir qué tipo hace falta: «no tengo coche» pide el segundo, «mañana libro» el primero.
Orden de las cláusulas y la coma
Las cláusulas pueden cambiar de orden. Si la de if va primero, lleva coma después: If I had more time, I would learn Italian. Si va al final, no hay coma: I would learn Italian if I had more time. Igual en el tercero: We would have caught the train if we had left earlier.
Consejo
Antes de escribir pregúntate: «¿Es sobre ahora o sobre algo que ya pasó?» Ahora: past simple tras if y would + verbo en la principal. Pasado: past perfect y would have + participio. Así no queda sitio para un would de más tras if.
Errores típicos
If I would have time, I would learn Italian.If I had time, I would learn Italian. tras if no va wouldIf we would have left earlier, we would have caught the train.If we had left earlier, we would have caught the train. en el tercero, tras if va el past perfectIf I knew about the party, I would have come.If I had known about the party, I would have come. para el pasado, past perfect y no past simpleIf the shop had been open yesterday, I would buy the bread.If the shop had been open yesterday, I would have bought the bread. en el tercero, la principal lleva would have + participioIf I was you, I would call her.If I were you, I would call her. en la expresión If I were you solo va wereIf she didn't work nights, she wouldn't been so tired.If she didn't work nights, she wouldn't be so tired. en el segundo, tras would va el verbo sin toWhat you would do if you won the lottery?What would you do if you won the lottery? en la pregunta, would va antes del sujeto
Preguntas frecuentes
¿Cuál es la diferencia entre second y third conditional?
El second conditional (if + past simple, would + verbo) habla de un presente o futuro irreal: If I had a car, I would drive. El third conditional (if + past perfect, would have + participio) habla de un pasado irreal: If I had had a car, I would have driven.
¿Por qué no se dice if I would have time?
En inglés would va solo en la oración principal; en la cláusula con if va el past simple o el past perfect. El condicional español «-ría» aparece en la principal, pero la cláusula con si lleva subjuntivo, y en inglés eso es past simple o past perfect: If I had time, I would...
¿If I were you o if I was you?
Para aconsejar se dice If I were you, I would... Es una expresión fija. En otras frases con I, he, she o it valen were y was: If I were / was taller, I could play basketball.
¿En qué se diferencia would have de could have y might have?
Would have indica un resultado casi seguro, could have una posibilidad y might have un quizás. If we had left earlier, we might have caught the train significa «quizás habríamos tomado el tren».
¿Se pone coma en las frases condicionales?
Sí, cuando la frase empieza por la cláusula con if: If you had called, I would have come. Si la cláusula con if va al final, no hay coma: I would have come if you had called.