This is the first part of a method for working on 16th note fills, which I developed for my intermediate students. It requires some selective reading, but in a constructive way- the same type of skill is required to read a chart or lead sheet. Use pp. 22-23 from Ted Reed’s Syncopation. I suggest running through Reed ex. 1-15, plus the 20 bar exercise before proceeding to the next numbered item.
Feel free to post any questions in the comments.