If you want a more thorough example of Agree in action, you might take a look at the updated version of the Pat must not have been sending flowers to Chris derivation. You had a version of this (but without Agree) in preparation for the midterm.

It’s possible that this is more detail than you want, but it at least should be sufficient detail to get a handle on what’s supposed to be happening if the examples from the book and the handouts seemed too inexplicit.