Final answer:
The sentence "Éramos una hermosa tarde de verano" is written in the imperfect form of the verb, describing an ongoing past action or situation.
Step-by-step explanation:
The sentence "Éramos una hermosa tarde de verano" is written in the imperfect form of the verb. In Spanish, verbs have different forms to express different tenses, and the imperfect tense is used to describe ongoing past actions or situations. The subject pronoun "Éramos" means "we were," indicating that the action or situation described in the sentence occurred in the past.
Learn more about Imperfect tense in Spanish