The passive voice is a misunderstood entity in the world of writing. It is unfairly judged by many authors. Some writers, without taking the time to get to know this grammatical structure, avoid it at all costs. Others use it ineffectively because they do not understand how it works. How can you get to know this mysterious literary device?  Read more at: 

http://www.grammarly.com/blog/2015/how-to-use-the-passive-voice-correctly-2/