Breakdown of El muro viejo fue restaurado por el gobierno.
ser
to be
viejo
old
por
for / by / through / in/during (part of the day)
el gobierno
the government
Questions & Answers about El muro viejo fue restaurado por el gobierno.
Why do we use fue (from ser) here instead of estuvo (from estar)?
In the passive voice, we use a form of ser + a past participle to talk about an action taking place. Fue restaurado focuses on the event: the action of restoring happened. If you used estuvo restaurado, it would describe the condition or state of the wall after the work was done (meaning "the wall was in a restored state").
Does restaurado have to match el muro or el gobierno?
It must match the subject of the sentence, which is el muro (masculine, singular). In the passive voice, the past participle acts like an adjective, so it always agrees in gender and number with the thing receiving the action. If the subject were feminine, like la pared (the wall), it would be fue restaurada.
Why is por used here to mean "by"?
Why is the order el muro viejo and not el viejo muro?