Masculine singular: (al) lui/ei = (al) său
Feminine singular: (a) lui/ei = (a) sa
Masculine plural: (ai) lui/ei = (ai) săi
Feminine plural: (ale) lui/ei = (ale) sale
I thought that "sa" is her? should the translation not be "Her water is salty"?
"sa" is used because the noun is feminine (in this case it's 'apa'). So the noun determines the possesive grammar form (in this case 'sa') and sa means: his/her/its.
Maybe this question is stupid...but when do you use just "sa" and when "a sa"? Thank you in advance to the person who is willing to answer me :)
I think it's a very good question.
I'd say we use 'sa' when next to the noun: 'rochia sa' ( her/his dress)
But if you already introduced the dress you can also just refer to it by who owns it: 'a sa e albastră' ( hers/ his is blue)