Hasta que

Question

Why does hasta que cause the subjunctive. For example: hasta que vuelvas

Sidebar: what does tal vez mean and why does it activate the subjunctive (a website I was on said so)

Answer 1

Heidi already said it, but there we go again: the subordinate says "you return" (vuelvas). Are we saying that you have returned in the phrase "until you return"? No, we are saying that when (and if) you return, something will happen, so you can't declare it, and therefore, you can't use indicative.

Answer 2

Why does hasta que cause the subjunctive. For example: hasta que vuelvas

As Laza always says, you are not declaring anything, this is just a guess, as you might not even come back.

Te lo guardo hasta que vuelvas. I'll keep it for you until you come back.
Will you come back? Who knows.....

what does tal vez mean and why does it activate the subjunctive (a website I was on said so)

Tal vez, ojalá, quizás.....all trigger subjunctive.

Tal vez: tal vez -> perhaps, maybe

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