좋은 친구가

a good friend

→ 좋다
phrase Rare #31,830
a good friend 가 marks 좋은 친구 as the subject of the sentence.
KO: 좋은 친구가 항상 곁에 있어요.
EN: A good friend is always by your side.

대신 난 지나 랑 좋은 친구가 됐어요

But I did become good friends with Gina.

— 붉은 돼지 (1992)