Did you knowingly write what you wrote with the intention of mixing up some obscure difference in grammatical rules between British and American English? If not, he was calling you out for bad grammar, not because you were writing in the Queen's English. If you were aware, you still just mixed up two dialects while writing, which is a horrible fucking idea and a poor use of the English language.
When I write and speak in French, I use a Parisian dialect and I stick to it. I don't throw in things from Quebecois.
When I write and speak in French, I use a Parisian dialect and I stick to it. I don't throw in things from Quebecois.