expostulate about

expostulate about someone or something

 and expostulate on someone or something
to comment or argue intensely about someone or something. He always seems to be expostulating on something. Why can't he simply say "Yes" or "No"? Sam is expostulating on Bill's many shortcomings again.
References in periodicals archive ?
In the West, far too many commentators expostulate about Islam who have no knowledge of Arabic.