认识 (rèn shi): 知る; 認識する; よく知っている; 知り合う; 知識; 理解; 認識; 認知; 知っている; 見分ける; 理解する; 知識がある; 知識; 理解; 認知

I know that doctor.

Do you recognize this character?

We met (got to know each other) at university.

Regarding this issue, my understanding is still insufficient.

Although he doesn't know me, he is very friendly to me.