In this question, user mjjf correctly comments that the answer can be found on a question asked on ELU. Given how closely linked ELL and ELU are, it feels like the ELL question should be "closed as duplicate"... but there isn't a duplicate on this stack exchange, only on another related one.
Should we close the question? If so, how should we close it, given that you can't select a question on another stack exchange? If not, should we basically copy the answer over here, maybe rewriting it slightly to avoid plagiarism? That doesn't seem right to me either.