Las puertas son _________ todos los días por mi madre. (cerrar)

The sentence uses the passive construction “son + past participle,” and the participle must agree with “las puertas,” which is feminine and plural. The feminine plural form of “cerrar” is “cerradas,” so the sentence is “Las puertas son cerradas todos los días por mi madre” (“The doors are closed every day by my mother”).

AI-written and checked against the verified answer.