DEAR MISS MANNERS: If a woman has made a luncheon engagement with a gentleman and she is late, how long should the gentleman wait before he leaves the restaurant? My reply, when asked by someone, was “at least 30 minutes.” Is this correct, or is there a time limit?

GENTLE READER: Although there was never a specific time limit, the question has been complicated by the advent of continuous communication. Half an hour to 45 minutes without any contact is a reasonable upper limit. But if the lady calls, apologizes profusely -- and explains that she is caught in traffic but expects to be there in 46 minutes (according to her GPS) -- the gentleman is expected to accept the apology gracefully.

He can use the intervening time to contemplate whether the behavior is likely to be repeated if a subsequent invitation is proffered, and the lunch itself to judge whether it is worth the wait.

DEAR MISS MANNERS: I invited my 19-year-old niece on a trip to Colorado with my husband and our two daughters, aged 11 and 9. We are renting a house for 11 days with two bedrooms and a sofa bed.

I am not sure whether it is rude to have my niece sleep on the sofa bed the entire time, or to offer her the bedroom that I was planning to have my daughters use. My niece is a full-time student and does not have any money of her own.

Should I ask my brother, her father, to contribute to the costs of her food and entertainment while on the trip? Or since I invited her, should all the costs be my responsibility?

GENTLE READER: In common with cooking and airplane travel, etiquette is often easier when it is less spontaneous. (Miss Manners does not mean to disparage spontaneity; she merely observes that it sometimes results in extra trips to the grocery store, or home to collect the passport.)

The correct time to raise the sleeping arrangements is when the invitation is issued: “Dear niece, we are going to Colorado and we would love to have you join us if you are available. The conditions are somewhat primitive -- you would be on the couch -- but we would enjoy your company and think we will all have a wonderful time.”

If you have already made the invitation, then you will have to reissue it, saying that you’ve now discovered more about the house, namely the lack of sufficient bedrooms. Since you are the host, you are stuck with the cost, but, as you are not providing a bed, this seems fair. Your niece will no doubt reciprocate at some point, if not by paying for a family meal out, or sharing in the groceries, then by making herself charming and useful.

DEAR MISS MANNERS: What do you think of the following phone message I received from a friend? “Hi, too busy to talk. Just wanted to let you know I got some good news.”

It made me wonder what she would have said if I’d been there to pick up the phone: ”Sorry, can’t talk. Please answer later when I’m less busy”?

GENTLE READER: In that case, Miss Manners gives you permission to ask, “Did you call me at an inconvenient time?”

(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: Guests arrived at my house from two states away for a four-day visit. After a lovely afternoon and evening, I crawled into bed. I woke a few hours later to chills, body aches and a 101-degree fever. It was evident that I had the onset of the flu.

The next morning, I explained that I had come down with flu symptoms in the night. I spent the subsequent days of their visit excusing myself for naps, trying to prepare food and helping arrange sightseeing tours. I was miserable, a terrible hostess and fearful of being contagious, which I certainly was by the third day, when I had lost my voice and developed a cough.

In my life, it is likely to happen again, and I will find myself in this situation either as guest or host. What should all parties do in this circumstance?

GENTLE READER: Are you unaware that etiquette grants sick leave? Everyone else seems to know, considering how often people claim false illnesses to get out of meeting their obligations.

And there you were, really sick and valiantly plodding along. Miss Manners hardly has the heart to tell you that you were violating your primary duty to your guests: to refrain from endangering them. Instead of waiting on them, you should have been telling them that while you hated to cut short their visit, you would have hated even more to expose them to the flu.

And what were they doing -- besides watching you suffer? Human decency requires that they swallow their disappointment about losing a vacation and look after you, or find someone to do so -- and then leave.

DEAR MISS MANNERS: I live in Europe, and my city, which was not built to withstand hot summers, has endured increasingly suffocating temperatures each year. Most buildings lack air conditioning, as does the public transport system. I have seen several ladies using folding fans outdoors and on the subways.

I’d like to get one myself, but I was wondering whether there are any rules governing the use of a fan, or any places (such as in a meeting or theater) where it would be inappropriate or distracting to use one.

GENTLE READER: You would not believe how many rules there are in connection with fans. How you hold it and when you snap it form a language that enables you to give such wordless messages as “Come here,” “Go away,” and all kinds of flirtatious signals in between.

Fortunately for people who are hot only in the climatic sense, nobody remembers what they are. So you can fan away, as long as you keep out of other people’s eyes and lines of vision.

DEAR MISS MANNERS: I would like to know if a woman must remove her summer hat when in a restaurant. Or will she be considered a country bumpkin?

GENTLE READER: ”A country bumpkin”? Now there’s an insult Miss Manners hasn’t heard in a long time.

Ladies’ hats need not be removed indoors, except in their own houses, but these should be actual ladies’ hats. Baseball caps and other unisex or men’s hats must be removed -- a fact that does not seem to be known to many male bumpkins, citified or countrified.

(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: I am a single, older, divorced woman, and over the years, I have been the target of inappropriate advances and sexual comments by married male acquaintances. In the past, I have brushed these off, but I now feel that this lack of respect deserves a reply.

In addition, these men (and others) try to attract my attention by being “cute,” which I find most annoying. I do nothing that I can think of to attract this unwanted attention. I am friendly, open, and have an optimistic view of life that seems to attract these type of folks.

What is the appropriate response?

GENTLE READER: Just as there are levels of offensive remarks, from the tasteless joke to the smarmy compliment to the outright proposition, there are levels of responses -- from the cold stare to the abrupt and wordless departure, on up to “How dare you?” said loud enough to attract others’ attention.

Miss Manners assures you that when administered, these are more effective than any lecture about sexism, which such an offender is bound to take as cute.

DEAR MISS MANNERS: Butter rules, please.

Stick butter in a butter dish with a lid is common. But I really haven’t found anything I like to use for a round butter/canola oil spread, or heart-healthy spreadable butter products. I have some crockery-type dishes, some with lids, that look OK for everyday use, but not for holiday dinners.

If butter bowls exist, where do you find them? I can’t bring myself to just put on the table the plastic container the butter spread came in.

Also, could you discuss butter knives? If you buy a set of cutlery for eight, you get two butter knives. Does that mean four people to a butter knife? That doesn’t seem right. Where do the butter knives go on a place setting?

GENTLE READER: You don’t happen to have a butter curler, do you? No, Miss Manners thought not. Anyway, a spread might not hold a curl.

Forgive the digression. She was just pointing out that butter lends itself to whimsy. Butter curls are served on tiny individual round dishes.

But yes, there are round butter bowls with lids that come in fine china or cut glass, and you can find dozens of them online.

But you cannot expect your guests to share individual butter knives. The ones that are sold in sets are servers for everyone to use, cutting butter from the communal source. If the butter is intended for a vegetable, they can put some on the side of their plates.

But if you are serving bread, you might want to have bread plates to the left of the dinner plate, and to invest in individual butter knives, which would be laid crosswise on the bread plate, with the handle toward the diner. They need not match your set.

DEAR MISS MANNERS: I don’t understand why people are offended when a bridal shower invite indicates gift cards. I am OK with people asking for what they want; we look at registries where people do just that. What’s the difference? In my opinion, it saves time.

GENTLE READER: There is no difference. Like registries, this saves the donors not only time, but also from having to exercise thoughtfulness. If it is the bride’s desire to collect shopping power, free of sentiment, this should do it.

(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.)