I know that at this section of the book things may seem too technical, which is why I recommend reading this book for yourself. Through reading, the reader will be able to glean what is wanted and/or needed, and it won’t feel so technical. (Craft is important!) This section is overflowing with golden nuggets.
A technical golden nugget: “A simple method for distinguishing the kinds and functions of content in a poem is to imagine to content of a poem in the shape of a cross…”
A simplified version of the cross Jack speaks of looks like this: