Breakdown of Nos encantó que el estadio vibrara.
el estadio
the stadium
que
that / than
nos
to us
encantar
to love (something)
Questions & Answers about Nos encantó que el estadio vibrara.
Why does this sentence use the imperfect subjunctive vibrara?
The main clause expresses a past emotion (Nos encantó). Whenever a past-tense verb of emotion, doubt, or judgment is followed by que and a change of subject (from "us" to el estadio), the following verb must be in the imperfect subjunctive.
Since "we" loved it, why isn't the first verb conjugated as nos encantamos?
Could I use the present subjunctive (vibre) if we still love the fact that the stadium vibrated?
No, Spanish follows strict rules for the sequence of tenses. Because the triggering verb is in a past tense (encantó), the dependent verb must also be in a past tense, regardless of whether you still feel that emotion today.
Is it also correct to say vibrase instead of vibrara?
Yes, vibrase is the alternative form of the imperfect subjunctive and is grammatically identical to vibrara. However, in Latin America, the -ra endings are vastly more common in both everyday speech and writing.