If you’ve been writing long, you’ve heard all the evils of using the passive voice. It sneaks into our prose without permission, and disguises itself among our active sentences like a nefarious chameleon. Unless you teach an English class, you might not even know what Passive Voice is, how to identify it, or how to remedy it. Consider that problem solved. Here is passive voice laid bare (if you’ll pardon the passivity of this sentence).
In order to understand passive voice, you must first understand subjects, verbs, and objects. Take a simple sentence: “A car hit a boy.” The subject is the car (because it is the noun doing the action). The boy is the object (because it is receiving the action). Active voice presents actions like this—Doer, action, recipient of action. Passive voice flips these so that the objective noun (here, the boy) becomes the subject of the sentence. “The boy was hit by the car.” In some cases, the doer is often eliminated. “A boy was hit.”
Passive voice is not incorrect grammar. Rather, it is a construction that emphasizes the object rather than the subject or neglects the subject altogether. However most editors don’t like it because it often weakens our prose. Readers like action, and with passive voice, the action is usually not emphasized.
The easiest way to fix passive voice is to flip the subject and the object. “The notion that this was a dream was washed away by his tears” becomes “His tears washed away the notion that this was a dream.” Make sense? In some cases, you may need to add a subject. “There was a text message from Sarah, the hot girl from Chemistry” becomes “Sarah, the hot girl from Chemistry, sent her a text.”
If you feel like you need a little more, these links will help you learn more about passive voice.
Gotta love Grammar Girl!
Purdue has some good online help as well.
Another good collegiate-level resource.