What tense is used in the following : “Elles étaient allées”?

Le plus-que-parfait, which corresponds to the “past perfect” in english.Used for actions or things that have occurred before a specific point in the past. It is actually pretty uncommon, and only really used when telling a story set in the past, and then talking about something happening before that time.In this example, we can recognise it by it’s distinct (2-verb) form.Firstly Either être or Avoir is used in the “imparfait” form, followed by the main verb in the past participle (participe passé).Here we notice être in “imparfait” : étaientFollowed by the verb to go in the past participle:alléesSo this is indeed in “plus que parfait” , and the resulting sentence means “they (feminin group) had been - “