I’m writing a story in the format of an “autobiography” from the point of view of my MC who has a rough upbringing and doesn’t do well at school. In fact he drops out in his mid teens. He’s not dumb as such. Just limited in terms of words, spelling, grammar etc and I’m not sure how to portray that realistically but also still be readable. More of his background: Born and raised in a run down trailer park, filled with poverty. His dad left when he was a baby. His mom is young and cares more about partying and therefore is negligent. His grandfather is around and helps to bring him up but he isn’t a great role model and dies when my MC is around 7 years old. In the trailer park the kids are free to run riot. Little to no discipline. No respect for their surroundings. No real ambition in life I hope I’ve posted this in the correct thread
Well, I'm not exactly an expert in this but if I had to throw in my two cents, a good place to start might be to look into the words he would've known when he dropped out of school. Also consider the words he could've picked up in say his line of work or around where he lives. If you haven't already, I'd recommend reading Flowers for Algernon. Granted, the character there and your character are both very different, and it is an epistolary novel, but it should give you an idea of how to write a character with poor grammar/spelling/a limited vocabulary while still keeping things engaging for the audience.
It's important to remember that you are writing your story, not your character. You might want to make this character your narrator, but that doesn't create a pass for bad writing. Your character in not writing the story. The character is something you've made up to better tell a story.
