Learn Spanish (Latin America): La euforia dominó el lugar antes de que abrieran la tienda. - Euphoria dominated the place before they opened the store.

The phrase antes de que always triggers the subjunctive because it sets up an anticipated event. Since the main action (dominó) happened in the past, the anticipated event must also shift to the past. This means we use the past version of the subjunctive, known as the imperfect subjunctive (abrieran).

Could I use the infinitive and say antes de abrir la tienda?

You could, but it would sound like the euphoria was the one opening the store! In Spanish, you generally use antes de + infinitive when the subject is the same for both actions. Because the euphoria dominated, but the store workers did the opening, there is a change of subject. That change requires antes de que followed by a conjugated verb.

The English translation says 'they opened', but there is no ellos in the Spanish sentence. How do we know who opened it?

The verb abrieran is conjugated in the 'they' form (third-person plural). Just like in English, Spanish often uses this 'they' form impersonally to refer to unnamed groups like staff or authorities, without needing to explicitly say ellos.

Why does the sentence start with La euforia instead of just Euforia?