Now You Know It: RSVP
In French, it means “Répondez, s’il vous plaît,” or, “Please reply.” Which just means that your host wants to know if you will attend.
When to reply: As soon as possible, within one or two days of receiving the invitation or, if RSVP deadline is given, by that date the latest.
How to reply: RSVP in the manner indicated on the invitation. If there is a response card, fill in and reply by the date indicated. If a phone number is given, make a call and be sure to speak in person. If an email is given, you may reply via email.
What do regrets only means?: In this case, you will reply only if not attending. By not responding, your host will expect you to attend.
Can you bring a guest?: Never ask! The invitation states the guests the host would like to include. No children on the invitation, don't ask. No date or partner on the invitation, don't ask. You have guests staying with you, better to decline and let the host know the reason, if they would like to include your guests they will let you know. If the invitation is open for you to bring a guest, while sending your RSVP, confirm your attendance and the attendance of your guest along with their names.
The correct wording when replying: Follow the wording on the invitation. If a formal invitation is received, reply in the same manner. For example, Mr. and Mrs. Smith accept the pleasure (or regret that they are unable to accept) your kind invitation for (occasion and date). If a casual invite is received, it is more appropriate to reply with a personal note. For example, Dear Henry and Mary, Oliver and I are delighted to accept your invitation to attend (occasion and date). Yours Sincerely, Ava.
Cancellations: Inform your host immediately should something prevent you from attending. Those reasons should be only health, death, a work commitment previously not known. Don't ever cancel one RSVP to attend a better opportunity to which you were invited afterward.