Perhaps 'see you'.
"Está a favor de su abuela", If you mean "He is in favor of his grandma". It you mean "he look something like his grandma", it is "Él parece como su abuela".
You say 'su amigo.' masculine. "su amiga", feminine.
SU means WITH
It depends how you intend the sentence.If you mean to say that your cat is a "masterpiece" in the same way that the Mona Lisa is a masterpiece, then it is "Su / tu / vuestro gato es una obra."If you mean to say that your cat gives you trouble, then it is "Su / tu / vuestro gato es desgraciado."
his is "su" but "su" (pronounced soo) has to be used in context since it can also mean hers and your, like you could say "El padre esta jugando con su hijo" Which translates "The father is playing with his son". He is "el" but can also mean "the". Confusing i know but you'll get the hang of it.
su cabello ( su is used for both her or his)
His as of his pants '' su pantalon''
Su autorización - Its okay
Su
comment as-tu su / comment avez-vous su
That ... they should dress up as santa.
Su hyun