Is üzgün for people and üzüncü for things?
Well, sort of. "üzgün" is synonymous with "upset" and "üzücü" is synonymous with "upsetting" :)
I see ! Thanks.
Only sad ? Upset is not accepted. why?
Upset works...it was just a missing translation.
Mutsuz and üzgün, are they synonyms?
I think yes, as mutsuz means "unhappy" and üzgün means "sad"