Passive voice

When I was in school, I wrote a few papers. Well, I remember writing MANY papers....Anyway, I never quite understood the instructor's criticism of my writing being in the passive voice. I'm still trying to grasp the notion. I know that sometimes I blog or email and feel like something is missing or not clear in my statements. Could that sneaky passive voice be there? I REALLY want to figure this out! I've been reading a web site about the passive voice - its beginning to make some sense....

Years later, degrees later, and might I add, many A's later, I'm going to figure this out! The passive voice and fractions - my issues. I might just need to hire a tutor.