Way 1 · best default
I'm so proud of you
Warm and direct. Best for family, partners and close friends.
Examples
You passed your driving test? I'm so proud of you!
I know how hard this year was. I'm so proud of you.
In a conversation
A: Mum, I got the place at uni!
B: Oh, sweetheart, I'm so proud of you.
Common mistake
Not: I proud of you.
Say: I'm so proud of you.
"Proud" is an adjective, so it needs "am": I'm proud. And it's proud "of", never proud "about" a person.