Read the sentence and write the passive voice using ser and the past participle of the verb. Las ventanas ________(limpiar) por el trabajador con agua, jabón y una toalla.
Answer : Las ventanas fueron limpiadas por el trabajador con agua, jabón y una toalla.
Translation: The windows were cleaned by the worker with water, soap and a towel.
Explanation: The passive voice in the past is performed with the verb "ser"+ past participle. In Spanish, participles, like adjectives, can carry gender and number marks, taken from the noun with which they agree. Here the noun referred to in the participle is "ventanas", this is a plural, feminine noun, so the participle must agree like that. Fueron limpiadas, which is the plural, feminine form of the participle.