Well, howdy there! Time to get down to brass tacks and suss out this here writin' style.
Our friend Billy is a country boy who is plainspoken and straight to the point. To further highlight Billy's youth and innocence, Billy often speaks in simple, short sentences:
A year passed. I was twelve. I was over the halfway mark. I had twenty-seven dollars and forty-six cents. My spirits soared. I worked harder. Another year crawled by, and then the great day came. (3.25-26)
Pretty plain, right? But don't be fooled into thinking he can't spin a good metaphor or simile when the moment calls, even if the imagery he uses is still pretty country: "By the time I had reached the river, every nerve in my body was drawn up as tight as a fiddle string" (8.42).
And that's all we have to say about that.