In Spanish, the passive voice is used to emphasize the action or the object receiving the action, rather than who performs it. It's formed by combining a form of "ser" (to be) + the past participle of the main verb. The past participle agrees in gender and number with the subject. Example: Active: El chef prepara la comida (The chef prepares the food). Passive: La comida es preparada por el chef (The food is prepared by the chef). Passive constructions are less common in Spanish than in English, and sometimes it's more natural to use reflexive constructions (called "pasiva refleja"). Example: Se vende esta casa