In sentences in active voice, the agent (the doer of the action) is the subject of the verb. In active sentences, there may or may not be an object (the receiver of the action).
Check out these examples of sentences in active voice. Hint: the subject (the doer) is highlighted in purple, and the recipient is highlighted in green.
Emilio escribe un libro.
Emilio is writing a book.
Yo hago un pastel.
I am making a cake.
Mi madre cocinó la pizza en el horno.
My mom cooked the pizza in the oven.
Los ingleses establecieron las colonias hace 200 años.
The English established the colonies 200 years ago.
Passive Voice
In sentences in passive voice, the receiver of an action gets moved to the subject position. This is often done to move the focus from the doer to whatever it is that was done.
Spanish has two passive forms: the passive with
ser
(to be) and the se pasiva.
The following formulas are used to create the passive voice:
ser + past participle (+ por + agent)
se + third person
In the passive sentences below, the doer of the action (highlighted in green) is no longer the subject. Instead, the recipient of the action (highlighted in purple) is the subject.
El libro fue escrito por Emilio.
The book was written in by Emilio.
La pizza fue cocida por mi madre.
The pizza was cooked by my mother.
Se establecieron las colonias hace 200 años.
The colonies were established 200 years ago.
Se hizo este pastel con miel.
This cake was made with honey.
Note that the last two examples above do not have an overt subject in Spanish. Both examples use the se pasiva, which is commonly used to say what an unknown or unmentioned they did.