Mi hermano y yo ________________ a la playa en el verano.

“Mi hermano y yo” means “my brother and I,” so the subject is nosotros (we). The preterite form of ir for nosotros is “fuimos,” making the sentence “Mi hermano y yo fuimos a la playa en el verano” (“My brother and I went to the beach in the summer”).

AI-written and checked against the verified answer.