Relax. This one's easy. Told from the perspective (and in the voice) of a teenager, Catcher in the Rye is about as hard as a conversation with your best friend—if your best friend actually paid attention in English class. Check out this totally random section:
I was only thirteen, and they were going to have my psychoanalyzed and all, because I broke all the windows in the garage. I don't blame them. I really don't. I slept in the garage the night he died, and I broke all the goddam windows with my fist, just for the hell of it. (5.7)
Sure, "psychoanalyzed" has five syllables. But other than that, there isn't a single word longer than two-syllables. Something else to notice? Almost all of the words are good, solid Anglo-Saxon words. There's hardly a Latin root to be found. Catcher in the Rye may not improve your SAT score, but the simple, straightforward language helps up get caught up in Holden's world.