Passive Voice

In passive sentences, the subject receives the action of the verb.  In active sentences, the subject does the action.  However, the meaning of both sentences is the same.  The passive voice in Spanish is formed with a tense of ser and a past participle.  Ser should be in the same tense as the verb in its corresponding active sentence.  The agent is expressed by por if the action is physical; and by de if mental.  The past participle agrees in gender and number with the subject.  If you use estar instead of ser, the past participle is called the predicate adjective and it is not a passive sentence.

Active	El viento destruye la casa.	The wind destroys the house.
Passive	La casa fue destruida por el viento.	The house was destroyed by the wind.
Predicate Adjective	Cuando la vi, la casa estaba destruida.	When I saw it, the house was destroyed.

El niño fue castigado por su padre.  The boy was punished by his father.
Rosa es amada de todos.  Rose is loved by everyone.