>>34205
I'm not sure I really knew my teachers. Maybe one or two from high school, in primary school I don't think was receptive enough to collect more than a couple of impressions. In uni, there were again a couple we talked more beside the lectures, and then it's like grown ups talking with grown ups. Well, almost.
Whom a person knows will depend on social circles, chosen educational specialization (a STEMmer will meet less grills in uni than one learning something from humanities) and job. For example I've a bunch of female coworkers whom I talk to frequently not just job stuff, so to some extent I know them well, better than simple acquaintances even if we aren't on friendly terms. Some better than others, and despite I don't like asking personal questions still I can pick up bunch of stuff, like what they eat, how they eat, what illnesses they have, personality quirks, their kids and parents and pets (and what illnesses they have, what their job, personality quirks), what they read, what they listen or watch, if they go to swim to X place but not the other and how many times, what is getting repaired in their homes or they built some shit in the garden, and bunch of gossip that makes my ears bleed, etc, etc. So a bunch of info one can put together a quite deep picture if he really wants.
Neighbours, one can know them too. Tho as people are more mobile nowadays and move easily they seem to make less connections with neighbours. We have new ones I know jack shit about them despite they are living around for years now. Which is a mistake since if something bad happens the closest people are neighbours, not their siblings living on the other end of the country. All right I'm getting far from the original point.
But one can live with gf/wife for a long time and not getting to know her well (even tho will know better than a coworker). Can be situations which make one look at her like a new person. There are hidden aspects of personalities.