는 잘 모르겠지만

I don't know much about …, but

→ 는
phrase Rare #25,420
I don't know much about …, but Used after a topic to say that you are unfamiliar with it before adding a contrasting point.
KO: 한국 역사는 잘 모르겠지만, 조금씩 배우고 있어요.
EN: I don't know much about Korean history, but I'm learning little by little.