So my brilliant high school English teacher taught at the same prep boarding school for over 40 years. He retired, and then the next day, he friended 40 years of alums on Facebook, where he has been an active and regular poster ever since. But what is really so great about this situation is--when questions like this come up, alums from the mid-70s to the mid-teens will just post these kind of grammar questions to his feed, and he'll answer them. Along with questions about TS Eliot or almost any other English-related questions. It's an amazing dynamic to watch unfold.