0 If you are or get acquainted with something, you know about it or gradually learn more about it. -- conocer algo/familiarizarse con algo
I’m not acquainted with this writer’s work.
1 If you are acquainted with someone, you have met them but do not know them well. -- ser conocidos, conocer a alguien
Are you two acquainted?
2 If you get acquainted with someone, you gradually get to know them better. -- conocerse, conocer mejor a alguien
3 familiar with sb because you met before -- conocidos
Are you two acquainted? ¿Son ustedes conocidos?
4 familiar with -- familiarizado con
to get acquainted with the new software familiarizarse con el nuevo software
