for my ears this sounds strange could i say about instead of :of
I'm pretty sure you can.
mówimy o tym mężczyźnie
why tym not ten or tamten?and what is the diffrent?
As usual: cases.
"o" = about takes Locative. So the masculine, Locative version of "this" is "tym".
What is the case of man here ?
Looks like biernik but i couldn't be sure.
It's locative. It's not used here to denote any location, but with „o” you use locative.
i would use in english we are talking about that man.
I changed it to "about", but "talking" (while obviously correct) may easily suggest a conversation ("rozmawiamy"), so let's leave "speaking" as the main answer.
I'm pretty sure you have to, actually.
No, it's a completely fine English phrase, although I'd go with 'about' as well.
It's correct English but sounds rather Victorian