The Pluperfect Subjunctive

The Congiuntivo Trapassato expresses a past action that happened before another action in a past main clause. It is also crucially used in the hypothetical clause (the if-clause) of a Third Conditional sentence (Periodo Ipotetico dell'Irrealtà) to describe a past condition that did not happen.

Formation

It is formed using the Congiuntivo Imperfetto of avere (avessi, avessi, avesse...) or essere (fossi, fossi, fosse...) combined with the past participle of the main verb.

Usage Examples

You will frequently see this in sentences like: Non sapevo che lui fosse partito (I didn't know he had left - action completed before the knowing) or Se avessi studiato, avrei superato l'esame (If I had studied, I would have passed).