The Past Conditional is used to express a possible future action related to the past.

Examples:

Affirmative Form:

• Si hubiera salido tarde, habría perdido la oportunidad laboral (If I had left late, I would have missed the job opportunity)
• Habría surgido un problema si no se hubiese aclarado el malentendido (There would have been a problem if the misunderstanding hadn’t been clarified)
• Con un buen clima, habríamos caminado 20 kilómetros (With good weather, we would have walked 20 kilometers)
• Ella habría preferido el vestido rosado (She would have preferred the pink dress)

Negative Form:

• Si no hubiera salido tarde, no habría perdido la oportunidad laboral (If hadn’t left late, I wouldn’t have missed the job opportunity)
• No habría surgido un problema si se hubiese aclarado el malentendido (There wouldn’t have been a problem if the misunderstanding had been clarified)
• Con un mal clima, no habríamos caminado 20 kilómetros (With bad weather, we wouldn’t have walked 20 kilometers)
• Ella no habría preferido el vestido negro (She wouldn’t have preferred the black dress)

The Past Conditional conjugation of the model regular verbs (ar, er, ir) is: