DEAR MISS MANNERS: When did "RSVP" cease to mean "Please respond, yes or no" and come to mean "Respond only if your answer is yes"? I receive a lot of e-vites and such, and they all seem to imply this new interpretation of the old phrase.

It feels a little rude not to be offered a gracious way to opt out that doesn't involve not responding at all.

GENTLE READER: Can we please do away with that form? Apparently nobody understands it -- did everyone fail high school French? -- and it is now annoyingly used as a noun.

It means "please respond."

Yes, as those of you who did ace high school French will point out, the phrase is actually "if you please," but the "if" is not supposed to be taken literally. It is safe to presume that few people, even those who give large parties, can prepare adequately when they do not know how many guests they will have.

Miss Manners would think it obvious that it is rude to ignore an invitation. But most people only seem to find that out when they are the hosts.

So let's put it in plain English: "Please respond." The more formal version is "The favor of a reply is requested." Notice that Miss Manners does not use the British spelling, "favour" -- why all the foreign phrases? -- nor does she condone "Regrets only." It is not for the host to presume that a prospective guest would regret skipping the party.

DEAR MISS MANNERS: I had a "friend"/co-worker stab me in the back and betray my trust. She has no clue that I know, and she keeps asking/pushing me to go to lunch with her.

How do I politely decline so as not to cause friction? I don't trust her and prefer not to associate with her, but unfortunately I see her regularly.

GENTLE READER: Probably any other adviser would tell you to have it out with this person, explaining that you were hurt by her betrayal.

Not Miss Manners.

At best you would get an apology, which would not necessarily ensure its not happening again. But you might instead get a denial, a justification or a counter-accusation. If she really regretted what she did, she would have found a way to make that clear.

You have to work with this person. You have discovered that she is not a friend. So treat her only as a co-worker. That means that politeness is required, but not warmth -- nor lunch, nor other opportunities to talk it out. "Sorry, I'm busy" is all that is needed.

DEAR MISS MANNERS: I want to thank the U.S. Postal Service for delivering a card addressed to me by my mother, who was severely visually impaired. Her handwriting was terrible and this letter was handled with TLC to get it to me!

This was the last piece of mail I received from Mother before she died, and I am very grateful to those who recognized the love and effort that she put into sending it.

GENTLE READER: So do it -- thank your local post office, and perhaps write a letter to the Postmaster General. Miss Manners suspects that they do not get a lot of gratitude from the public.

(Please send your questions to Miss Manners at her website, www.missmanners.com; to her email, dearmissmanners@gmail.com; or through postal mail to Miss Manners, Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106.)

DEAR MISS MANNERS: About once a month, we go out to dinner with another couple and always have a good time. We tend to order roughly the same things -- one drink each, no desserts unless it's a special occasion -- so we just split the bill.

We were surprised, but fine with it, when they suggested that we should eat at their house next time instead of going out. We've all been doing a lot of creative cooking during the pandemic, and I offered to host the following time.

We had a nice meal -- but then they told us what our share of the cost would be! I'm in shock that our friends would be so stingy as to charge us for eating at their own home. We thought they were close friends!

GENTLE READER: Evidently, they are close. Or maybe just confused.

There is, indeed, a huge difference between a restaurant and a home. Or rather, there should be. But the habit of eating in commercial establishments has resulted in all but obliterating the meaning of private hospitality.

This shows up in many ways. Guests no longer feel obliged to make definite advance commitments -- perhaps even less than they do for restaurants, which may charge no-shows. They expect to be able to state their food preferences. They are not likely to reciprocate.

And hosts who no longer feel the sole responsibility for providing the meal may even assign some of the shopping and cooking to their guests.

Your friends have carried this to a crude extreme. To anyone who remembers the ancient tradition of hospitality, this is sad. Planning and overseeing entertainment was a pleasure that people enjoyed taking turns doing. The claim that it put all the burden on the hosts was false because reciprocity evened it out.

Miss Manners might have been inclined to make this point by asking your friends whether the price they quoted included the service charge.

But if you are not terminally insulted by your friends' having treated you as a customer rather than a guest, you could just set an example in your own house. The opportunity to discuss this will be when your friends ask what they can bring, or attempt to pay. Then you can properly express your horror: "No, no, it's our home, and we consider it a pleasure to entertain you."

DEAR MISS MANNERS: My neighbor is hosting a brunch for a local mother who lost her daughter in early December. The daughter was tragically murdered, leaving two grown sons and a 3-year-old. It was terribly painful for the entire family.

My husband and I are of the belief that it is too soon for this event. Please help me sort this out in my mind.

GENTLE READER: It is not for outsiders to decide what constitutes a proper period of mourning. If it were too early for the bereaved mother to be coaxed out to what may be a low-key event, that lady could have begged off.

Life was simpler, Miss Manners agrees, when society set firm periods for withdrawing after a death, but these were not always what best suited the individual. The way for you to come to terms with this is to acknowledge that you cannot know the survivor's needs, so it is best to let her decide whether this is too soon.

(Please send your questions to Miss Manners at her website, www.missmanners.com; to her email, dearmissmanners@gmail.com; or through postal mail to Miss Manners, Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106.)

DEAR MISS MANNERS: My mother cannot recognize the realities of my life. My husband lost his job four years ago; we eke by with thoughtful spending and renting out our guest room. I work overtime whenever I can, so we can have little luxuries like a streaming service subscription and quality food for our pets.

My mother is fully aware of our situation, and though she has given us cash in the past, she prefers to buy me clothes for "stepping out" as gifts. These clothes are definitely more her taste than mine (plus, she knows we never go out). She includes a gift receipt so the clothes can be returned, but often only for a gift card at a store I would normally never shop at because they don't carry anything I need.

Returning the clothes involves spending hours of my scarce free time taking a bus (we don't have a car), hauling awkward boxes and then scouring the store for ways to spend the credit. All the while, I'm thinking, "That could have bought a month's worth of groceries, or paid the vet bill."

Gifting these clothes allows my mother to live in a fantasy where her child has a vibrant, cosmopolitan lifestyle instead of the less glamorous reality.

Of all the complaints between child and parent, this seems very minor. But her denial of our situation makes me feel unseen, unheard, and that I embarrass her. Is there a kind way to communicate that her gifts are a burden? And that the most welcome gift from a more well-off and well-meaning mother is to send cash?

GENTLE READER: Is it maybe just possible that rather than shame you, your mother is trying to give you these small luxuries because she knows you would not indulge in them yourself?

That is, after all, what presents usually are -- not taunts and humiliation over a life she deems clearly out of your reach.

What you are suggesting instead is that she give you financial support. If you want to ask for that, Miss Manners would not stand in your way. But she does take objection to ascribing unkind motives to innocently given presents -- no matter how unusable and misguided those presents may be.

DEAR MISS MANNERS: I am invited to a 60th birthday party for twin sisters, but I only know one of them. Should I bring gifts for both or just the one I know?

GENTLE READER: For twins under 12, bringing a present for both of them to share would be a gracious thing to do.

But at 60, unless the two sisters live together, it is no longer practical or age-appropriate. Miss Manners therefore condones bringing only a present for the sister you know, with the presumption that the other sister's guests will pick up the slack.

DEAR MISS MANNERS: Why do you keep one hand below the table when you're eating?

GENTLE READER: So that it can keep watch on your wandering elbow.

(Please send your questions to Miss Manners at her website, www.missmanners.com; to her email, dearmissmanners@gmail.com; or through postal mail to Miss Manners, Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106.)