Why is "That / this letter is about my subject" incorrect? All advice welcome :D.
I believe that the liason of 'est' is actually optional, and depends on the region/dialect, so not necessarily.
This is interesting, since I've heard differently. My teacher actually explicitly said that this is a north-south divide, where in the south of France the liason is used, whilst in the north it normally is not.
I'd be interested in hearing if any other natives have opinions on this? My teacher could be wrong of course, or just speaks with some specific regional accent, but I'd like to find out.
I can see this sentence structure being useful in daily conversation. Does the same rule apply to all object or just people e.g. does "Ce livre est a pomme sujet" work?
"this letter concerns me". I know it could be taken differently, ie I'm worried about this letter, but can it not mean the same as "about me" or would "concerner" need to be used in the french sentence..? just curious..
To say 'That letter is about me', can this be spoken in two ways? Cette lettre est a mon sujet Cette lettre est de moi
I would always think that if the letter was mine, I'd write, "cette lettre est a moi" <-- the the accent above the 'a'. :). Maybe both. :)
And that I'd translate with "That letter was to me" Maybe all these phrasings have something funky with it.
I'm pretty sure either "....est de/à moi" are acceptable for expressing possessio, but as Progressor says, "à moi" is somewhat more typical/colloquial. It might become a little more complex when talking about a something like a letter which is given and received. "Cette lettre est la mienne" might be the best option to unambiguously express possession.