N1Grammar- studying differences between similar expressions

Thanks for the review.  It looks good and I'm going to pick up a copy.  My vocabulary is fairly large and I read Japanese nicely (at least Light Novels) but when it comes to definitions and nuances between points, I find the English helps.

By the way, does anyone know the answer to my question a few posts up about what a 働きかけの文 is?  I find it in many Shin Kanzen Master explanations where these sentences can or can not be used with certain grammar.