Learn Hardcore Italian: Avremmo preso l'ascensore, se al pianterreno ci fosse stata la corrente. - We would have taken the elevator if there had been power on the ground floor.

Avremmo preso is the condizionale passato (past conditional) of prendere. It’s formed with the conditional of the auxiliary verb (avremmo) plus the past participle (preso). You use it to express an action that would have occurred in the past under certain conditions.

Why is ci fosse stata in the subjunctive (congiuntivo trapassato) after se?

In third-type (counterfactual past) conditional sentences, the se-clause requires the congiuntivo trapassato to show an unreal past situation. Ci fosse stata la corrente literally means “if there had been electricity,” indicating that this condition did not actually happen.

What is the function of ci in ci fosse stata la corrente? Can it be omitted?

Here ci is the locative particle used with the impersonal verb esserci (“there is/was”). It marks existence in a place. It cannot be dropped if you want to convey “there was electricity.”

Why do we use essere (fosse stata) as the auxiliary for corrente instead of avere?

Existential or state-of-being constructions (and many intransitive verbs) in Italian take essere as their auxiliary. Since corrente here expresses existence (“there was power”), its past subjunctive is formed with essere: fosse stata.

What type of conditional sentence is this, and what is its structure?

This is a third-type (counterfactual past) conditional. Its structure is:
• Se + congiuntivo trapassato (ci fosse stata…) in the if-clause
• Condizionale passato (avremmo preso…) in the main clause

Can the clauses be inverted without changing the meaning?

Yes. You can say Se al pianterreno ci fosse stata la corrente, avremmo preso l’ascensore. Just remember to place a comma after the se-clause when it comes first.

Why is it al pianterreno instead of just pianterreno?

Al pianterreno means “at/on the ground floor.” Italian uses the preposition a + definite article il to indicate location on a specific floor, so you need al.

Could we instead say prenderemmo l’ascensore se avessimo la corrente?

Yes, but that’s a second-type (present/future) conditional: it talks about a possible present or future scenario (“we would take the elevator if we had power now”). Our original sentence refers to a missed opportunity in the past, so it requires congiuntivo trapassato + condizionale passato.