Question

vosotros casarse

Explanation:

The problem involves conjugating the reflexive verb "casarse" (to get married) for the "vosotros" (you all, informal in Spain) form. In Spanish, the reflexive verb conjugation for "vosotros" with "casarse" is "os casáis". We take the verb "casarse", drop the "se" (reflexive pronoun for "vosotros" is "os"), and conjugate the verb "casar" in the "vosotros" present tense, which is "casáis", then add the reflexive pronoun "os" before the verb.

Answer:

os casáis