pluscuamperfecto del subjuntive

Question 1

what is it?

Answer 1

it is formed with the imperfect subjunctive form of haber and the past parciple

Question 2

haber conjugations

Answer 2

hubiera hubieramos
hubieras
hubiera hubieran

Question 3

when is it used

Answer 3

when the action of the verb in the subjunctive occurred prior to the action of the verb in the main clause

Question 4

conjugations other verbs

Answer 4

ado/ido