Answer:
In order to solve this exercise, several factor must be taken into account. You have to modify the verbs in the sentences by changing them into the past but you also have to take into account the personal pronoun suitable in each of these cases and the number and gender in the nouns contained in each one of the sentences.
Explanation:
¿cuándo / encontrar / (tú) / ese / corbata?
¿Cuándo encontraste esa corbata?
ayer / nosotros / oír / este / música / en la fiesta
Ayer nosotros oímos esta música en la fiesta.
Juanjo / venderle / aquel / libros / a Raquel
Juanjo le vendió aquellos libros a Raquel.
