For English, I have to write a research paper. My author is C.S Lewis. I wanted to write about the influence of his religious conversion on his works. But I can't only write about that. I have only read The Problem of Pain, The Screwtape Letters and the beginning of The Great Divorce... What else can I write for my research paper? Perhaps, something having to do with religion? And what else can I do so that my research paper can be good?