From J. R. R. Tolkien, in The Return of the King, Appendix F.
In those days all the enemies of the Enemy revered what was ancient, in language no less than in other matters, and they took pleasure in it according to their knowledge. The Eldar, being above all skilled in words, had the command of many styles, though they spoke most naturally in a manner nearest to their own speech, one even more antique than that of Gondor. The Dwarves, too, spoke with skill, readily adapting themselves to their company, though their utterance seemed to some rather harsh and guttural. But Orcs and Trolls spoke as they would, without love of words or things; and their language was actually more degraded and filthy than I have shown it. I do not suppose that any will wish for a closer rendering, thought models are easy to find. Much the same sort of talk can still be heard among the orc-minded; dreary and repetitive with hatred and contempt, too long removed from good to retain even verbal vigour, save in the ears of those to whom only the squalid sounds strong.