As I was writing some dialogue this morning, I ran into a peculiar little problem. I'm trying to write dialogue spoken by a teenage character (an eighteen-year-old girl), and I'm trying to make it as believable as possible. The line should be, "He's not capable of the evil of which he's been accused." Instead, I wrote, "He's not capable of the evil that he's been accused of." The first version is written more properly, but sounds stiff. The second, I feel, uses syntax more likely of a teenager. As a reader, if I used the second version, would you think, "Okay, that's how the character speaks" or would you think, "Jeez, this author can't write grammatically-correct sentences"? (Keeping in mind that I'm aware that the whole "don't end with a preposition" rule has been relaxed in recent years.) Of course, this is just one instance, but as I near the end of my book and look forward to the revision process, I can see myself tackling the issue a few times in the near future.