During the recent political debates, my wife and I were musing about whether "commentate" was a verb. "Commentators" are abundant in politics (and in sports), but we thought "commentate" would be a ridiculously elaborate form of "comment" in the way that "to orientate" is misused for the verb "to orient."
But "commentate" does exist. The link goes to the online Wiktionary; the hard-copy dictionaries in our house vary in this regard. Some don't list it, others cite is as "rare." (I do have the sense that if/when used, "commentate" would imply a simultaneous response to an activity - sporting event, news item - as opposed to "comment," which might refer to a long-ago event.)
I know there are readers out there who are proofreaders or have editorial experience and may have a well-thumbed Strunk and White on the bookshelf. Please feel free to commentate.