The Passive Voice

We use the passive voice when we want to put the objet first or maybe we don't want to say who did the action.

Sometimes what causes the action is unknown, unimportant, or obvious.

Example

• Active: I painted the house.
• Passive: The house was painted.

In passive voice you need the verb to be and the past participle.

Tense	Active	Passive
present simple	I make a cake.	A cake is made (by me).
present continuous	Karla is cleaning the house.	The house being cleaning by Karla.
past simple	Luis read Harry Potter.	Harry Potter was read by Luis.
past continuous	She was writing an e-mail.	An e-mail was being writing by her.
present perfect	I have made a mistake.	A mistake has been made by me.

Practice

http://www.curso-ingles.com/practicar/ejercicios/the-passive-voice

http://www.saberingles.com.ar/curso/lesson24/06.html

http://www.ejerciciosinglesonline.com/new-exercises/ex-1-passive/