I am writing a reading comprehension book for students. This book is for-profit. I would like to use excerpts from copyrighted literature books to set up comprehension questions as a learning exercise.
From what I've read, there would be 3 factors in favor of this being fair-use: 1) I'm using very small portions of each work 2) My re-use would not affect the market for the original work 3) I'm attempting to create something new from the original (the comprehension exercises).
Factors against fair use would be that this is a commercial project and that I would be using many excerpts albeit from different works. Overall, would this constitute fair use?