verb or noun
It is a common misconception that the American verb/noun"R.S.V.P." is a translation of the French phrase, "répondez, s'il vous plaît," or "please reply." In France, the person sending the invitation would like the recipient to accept or decline the invitation with a "oui" or a "non." In the United States, R.S.V.P. is actually an acronym debated by linguists to mean either "Request for Slew of Vague Possibilities" or "Reasonable Sounding Variations of Promises."
In the United States, the expectation is that the invitee will respond with a series of possible scenarios that may or may not play out in the future, without ever actually accepting or declining the invitation. The more invented but plausible situations described, the luckier the inviter will feel if the invitee actually shows up to the event; this is also a way to mitigate any ill will if the invitee fails to appear - she clearly had a lot of things possibly going on.
The fear of being beholden to one's own plans, like dinner with friends or a family christening, will keep even the most planbitious from committing to anything verbally, much less in writing, making wedding season and tax season feel like an endless barrage of paperwork where someone wants your money.
I'm so sorry I haven't RSVP'ed yet, I'm just trying to figure out where I'll be on Saturday because I have a work event the night before and we all know how those go. Also my grandma will probably be really sick and it might make me sick and I've just had so much going on lately, no time to even do laundry!
So... you're coming?