Final answer:
The correct preterite verb to fill in the blank in the sentence is 'fui', which means 'I went' in English.
Step-by-step explanation:
The correct preterite verb to fill in the blank in the sentence 'a la playa con mi familia el verano pasado' is fui, which means 'I went' in English. The sentence translates to 'I went to the beach with my family last summer.' The verb 'fui' is in the preterite tense, which is used to talk about completed past actions.
Learn more about Spanish verbs