Present Perfect Subjunctive _ pluscuamperfect

							 Present Perfect Subjunctive ~ Perfecto de subjuntivo
The present perfect subjunctive, also known as the past or perfect subjunctive, is used
when a verb or expression requiring the subjunctive in the main clause is in the present,
future, or present perfect. You might notice that the same definition holds true for the
regular (present) subjunctive, so what is the difference? The present subjunctive is used
when the dependent clause is in the present or future, while the present perfect
subjunctive is used when the dependent clause is in the past.

For example, if you want to say, "I doubt you'll do it," you'd use the present subjunctive:
Dudo que lo hagas. But if you wanted to say "I doubt that you did it," you'd use the
present perfect subjunctive: Dudo que lo hayas hecho. Another example: "It's good that
he is studying" - Es bueno que estudie vs "It's good that he studied" - Es bueno que haya
estudiado.


Pluscuamperfecto de Subjuntivo - Spanish Pluperfect Subjunctive

The pluperfect tense of the subjunctive mood is used to express the same subjectivity as
the present subjunctive, but at a point before another action in the past. The pluperfect
subjunctive is used in three main ways:

1. To express subjectivity in the past after the same verbs, impersonal expressions, and
   conjunctions as the present subjunctive. For the pluperfect subjunctive to be needed,
   the verb in the main clause has to be in one of the following tenses/moods: preterite,
   imperfect, or conditional.
    Quería que tú lo hubieras hecho.                I wanted you to do it.
    Fue una lástima que no hubiera podido           It was too bad that he could not come.
    venir.
    Estaba triste de oír que su padre hubiera       It was sad to hear that his father had
    muerto.                                         died.


2. To express a wish, after ojalá que, that something had happened differently in the
   past.
    Ojalá que hubiera ido.                          I wish he had come.
    Ojalá que hubiéramos podido verlo.              If only we could have seen it.


3. In conditional sentences (si clauses).
    Si hubiera sabido, habría ido contigo.          If I had known, I would have gone
                                                    with you.