Answer:
Nosotros fuimos, Ustedes asistieron
Explanation:
When the word 'Anoche' is present, the preterite tense is typically used. Therefore:
If saying "We went to the movie theater" and "You all attended a concert", the verbs used would be:
Nosotros fuimos- "We went"
Ustedes asistieron- "You all attended"
The endings are standard -ir verb endings.
Yo-Prefiero
Tu-Prefieres
El/Ella/Usted-Prefiere
Nosotros(as)-Preferimos
Ellos/Ellas/Ustedes-Prefieren
The stem-change is e-ie with the second e (preferir to prefier-). This occurs in all conjugations of the verb but the nosotros(as) form. This is the same with all stem-changing verbs in the present tense.
Hope this helps!!