You have a legitimate question, but unfortunately there is no simple, clear answer. Of is one of our pesky little prepositions that are best learned in context and committed to some "logical" order in each student's mind. I think the most common use is to show possession.
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.
Philip Let's see if one of our other teachers can come up with categories of its use.I'm not even going to begin to try. I suppose the broadest category might be roughly that connected with an idea of 'belonging/possession' but that's about it for a short answer.