If it's just a random thesis:
Topic: Dog Fights
Thesis: Dog fights should be illegal, since they are a cruel way to abuse dogs for profit.
Opposing Thesis: Dog fights are entartaining, and should be continued.
Compare to something you read in this unit such as "Two kinds" or more...
Well, when you're reading something, the words are being read aloud in your head. That voice is the 'voice' that we talk about in school. It's the style and word choice of the person who's writing it, and how that gets translated into our heads as a character speaking. Hope this helps! c: