San could be translated into mr/ms and you drop it off pretty much only when you’re close enough with the person you’re describing. If you use just the last nam

San could be translated into mr/ms and you drop it off pretty much only when you’re close enough with the person you’re describing. If you use just the last name it will sound “Oh yeah, i had meeting with Mikey” if you’re referring to person called Mike Miller. First name is usually only used by really close friends and lovers. The other time is when you’re using some other suffix with them, eg. you refer to them by profession.