Or at least, that I don’t grasp in the same way other people seem to:
Connotation.
Embarrassment.
Offense. (Being offended by [something]. What makes [something] offensive.)
Apology.
RSVP…. -ing?
The way other people experience these things and react to them, all I can say with confidence is that I do not share their experience and understanding. I don’t get it. Sincerely. Reading the definitions … doesn’t clear things up at all. I think it’s related to that first one, ‘Connotation’ – ie: that these concepts have connotations of which I am not aware and have not yet figured out how to understand. Importantly, connotation itself is on the list, because I don’t really grasp it, either. How do people detect when they should go to these mysterious alternate meanings instead of the definitions of the words, and how do people know what those meanings are? I don’t get it. Never have, really.
How can you not understand RSVP'ing. I mean I've met you so the middle three I understand YOU not grasping. But RSVP is a fairly simple concept.
I am having a party and invite 50 people. I don't know who can make it so I ask that they tell me in advance so I can purchase the correct amount of food, drinks, party gifts, etc. With out this information I don't know if 2 or all 50 are coming. Why buy a sheet cake if I only need 6 cupcakes. It is most commonly used to save money or at least use the budget most wisely. For example: April bought 6 cases of wine for the wedding but only 3.5 were used. A better understanding of who was coming could have saved her at least $60.
Or am I misunderstanding what you don't grasp?