If you’re writing a book, you should know The Chicago Manual of Style (CMOS) is the standard editorial guide in book publishing. All professional editors refer to it as they create a unique style sheet for each book that lists a publisher’s and author’s preferences (e.g., spell out “okay” or just use “OK”? Show possession as “Charles’ house” or “Charles’s house”? Put an author’s Acknowledgments page at the front of a book or at the back?).

I recently completed two copyediting tests for traditional publishing houses to earn a spot in their freelance pools: one for a Big Five publisher and one for an independent press. I only “passed” one of them. Here’s what happened.