not know (a fact or piece of information), not know someone; not be acquainted with someone, to have never experienced firsthand
I was looking at the directory because I didn’t know where the resident’s room was.
— REC / レック (2007)
Young people these days are different from how they used to be—they don't know how to be patient.
— イル・ポスティーノ (1994)
Someone who doesn't know the desert wouldn't understand that it's just an ordinary place, too.
— イングリッシュ・ペイシェント (1996)