That's not very typical. (Pun intended, and John Clarke reference intended too.) It was just a mistake. Given the topic, it's possible that that was written by

That's not very typical. (Pun intended, and John Clarke reference intended too.) It was just a mistake. Given the topic, it's possible that that was written by someone who's not a native speaker - but whose writing is otherwise very good. (And arguably better than that showoff sentence!) As you noted, a native American English speaker would write "...a language whose reach..." And that's that. RIP John Clarke: https://www.youtube.com/watch?v=3m5qxZm_JqM https://www.youtube.com/watch?v=3m5qxZm_JqM