So why should you use the passive voice? Well there are times when you don’t want to say who or what did the action. Maybe you’re trying to avoid responsibility for something you did or you don’t want to get your mate into trouble. Or maybe you don’t know who did the action or because actually the object is the most important or the most interesting part of the sentence. So that’s the thing that the action is happening to not the thing that is doing the action.

You can use the passive to change the focus of your sentence. So let’s go back a moment. To understand the passive voice, I should really first explain the active voice but you already know it, it looks like this.
The children ate the cake.
Subject, verb, object. Now most English sentences are more complicated than this but we’ll start simply. The subject does the action to the object.
Now, imagine that you left for work in the morning and there was a whole cake on the kitchen table. But by the time you got home, it had completely disappeared. You don’t know who ate it, I mean you could probably guess, but you don’t know.
Where is the cake? The cake was eaten by somebody.
