I came across a phrase today that needed to be changed: "... including presentation of data in writing, speaking, and graphically."
So, immediately, I knew the problem: the list items were non-congruent: (gerund noun, gerund noun, and adverb). The thing to do was to bring them all to the same type of list items, all nouns or all adverbs. I initially thought that it would be good to write them all as adverbs: graphically remains as it is, while speaking changes to verbally... but writing changes to... what?
My first thought was that, like I did when substituting verbally for speaking, it would likely require that one change the word itself from the Old English-derived word, writing, to a Latin-derived word. However, which Latinate word had an adverb for what "writtenly" (which doesn't exist as a word) would correctly express? Going to thesaurus.com, I was presented with several synonyms, but I did not recognize any that had an adverb form.
I eventually came up with literarily as the closest option that I could find, but it wasn't really useful, since it had a strong connection with the terms literature and literate; the written word, or the ability to read and write. However, the only other option appeared to be the adverb phrase "in writing," as in the phrase, "Please submit your comments verbally or in writing."
Since the best suggestion of using adverbs would have been, "... graphically, verbally, and in writing," (which I don't like for stylistic reasons), I ended up suggesting, "... in speaking, writing, and graphing." (The justification of changing from "graphically" to "graphing" was due to the fact that the paper was discussing the necessity to be able to show data in graphs; if it were based on something else -- such as the ability to use illustrations that aren't necessarily graphs -- then I would likely have suggested using the [less stylistically choice] adverb list.
EDIT (2014-08-14): I came across advice on this topic from "English Language & Usage", in which various people suggested textually and orthographically. However, in the above example, I don't think that either of these adequately capture the meaning that was being communicated. Textually refers to actual written words that already exist (as opposed to text that may yet be produced). Orthographically refers to the part of the written language that has to do with correct spelling. In short, both of these options could work, and might be of use to some people, but they are not to be considered generally synonymous with the adverb phrase "in writing."
EDIT (2014-07-01): Upon further reflection (no I couldn't let this go), I would now suggest "graphically, verbally, and in writing." My feelings on the stylistic "necessity" of parallel structure outweighing the simple fact that there are perfectly adequate adverb forms for "graphic" and "verbal" have changed. Ah, well, writing style preferences are fickle, it seems.