Final answer:
The correct verb to complete the sentence is "fuimos" which means "went" in English.
Step-by-step explanation:
The correct verb to complete the sentence is fuimos. The sentence "Fernando y yo fuimos al mercado el domingo pasado" translates to "Fernando and I went to the market last Sunday". The verb "fuimos" is the past tense conjugation of the verb "ir" (to go) for the subject "nosotros" (we).
Learn more about Spanish verb conjugation