when i was in the 5th grade, our creative english teacher walked calmly to the board and wrote the word "GO." we all looked at it for awhile, and then she told us "this is the GENERIC word 'go'." after we learned what "generic" meant, our task was to come up with a list of other words we could use instead of "go" that would be specific, more descriptive. the list began: walk, run, amble, drive, skip, fly, scurry, leave, hurry, scatter, split, boogie-ok, some of them i'm making up now. but each one evokes an image. it's a picture of going that adds excitement to the language. when you're given a lead sheet, say from your songwriter friend, or a page from the real book or whatever, and the chord says "C," what else could you play? Cmaj7, Cmaj9, maybe it belongs in the dominant family: C7, C9, C7b9. maybe it doesn't really need a 7 in it, but Cadd9 might be a nice color to try. if the next chord is D minor, would Dmin9 work? or Dmin11? sometimes a lead sheet offers a general outline of a tune, but it is up to us to interpret it musically, tastefully, adventurously perhaps, or with restraint perhaps. each context calls for its own descriptive sound. what word could we choose that makes our story telling vivid and alive? what variation of a chord could we choose that makes magic with a melody? how many fingers do you have left over-what happens if you put one right there...