DEAR MISS MANNERS: Twice in one week I have been compared to two celebrities who look nothing like me, or each other! One friend continued to insist that I look like said celebrity even when I politely ignored him and changed the subject. He even referred to her as my "twin."

To add insult to injury, neither of these two celebrities share my hair or eye color (I am a redhead with green eyes). Furthermore, I consider one of these actresses to be ugly. What is the proper response to unsolicited comparisons like these?

GENTLE READER: Presume that the intention was to compliment you, and tell these people "thank you." If you do not agree with the celebrity comparison, Miss Manners permits you to punctuate that thank-you with a question mark.

DEAR MISS MANNERS: I'm at a loss as to how to take care of household chores when we have houseguests.

We regularly get visitors (sometimes family, sometimes friends) who may stay a few days, a week or two weeks. The house is clean when they arrive, but I try not to do any house cleaning, other than cooking and washing dishes, while they are here.

The house can go several days without cleaning, but eventually it starts to show (especially with the floors and bathrooms). I don't know what to do about it.

If I start cleaning while they are sitting and relaxing, their discomfort shows at watching me clean around them. If they help me clean, I feel bad about turning my guests into servants. If I don't clean, I must look like a poor housekeeper, and the house becomes uncomfortable.

It rarely happens that I can wait until they go out somewhere, because we are always together. Today I tried waiting until everyone was in bed and did some general cleaning in the bathroom, but then I was worried I was making too much noise, and that definitely won't work with vacuuming.

GENTLE READER: If guests are staying more than a few days -- particularly if they are doing it repeatedly -- Miss Manners considers them to be more temporary residents than visitors, and they should be treated as such.

Clean when you feel the need to clean, prefacing it by saying, "Excuse me, but I just want to tidy up a bit." At that point the onus is on the guest to offer to help. You should not feel bad about accepting it, although giving them a few menial tasks is probably plenty. If they do not offer to help, then their discomfort is their own problem.

(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, Universal Uclick, 1130 Walnut St., Kansas City, MO 64106.)

DEAR MISS MANNERS: As I have a long career as a musician and music scholar, I may be asked my opinion of a performance. I reply with a measured response, a statement of approval or a sharp criticism.

However, as an audience member there are occasions when I feel obliged to express criticism of the performance, or of excessive approval exhibited by the audience when I believe their unison response lacks understanding.

Why should it be acceptable to give standing ovations, etc., at the close of passable performances, but not shouts of critique? I only refer to professional concerts, and not school or amateur performers. My wife says I am rude and feels humiliated upon these circumstances. My therapist comments: "Do no harm."

GENTLE READER: Online commerce has conditioned us to the unavoidable running commentary from "unsatisfiedcustomer447" on how the toaster did not work as advertised, but not every interaction with our fellow man is subject to review.

Nevertheless, curtain calls certainly are, and Miss Manners will defend your right to boo as well as to cheer.

But it is not a debate. The person sitting next to you has as much right to express his opinion as you, no matter how ill-informed it may be. Booing your fellow audience members would be impolite, and will, in any case, not be heard over all the "bravos."

DEAR MISS MANNERS: I received an email from a friend announcing that she would be eloping in two weeks.

This seems strange. Doesn't elopement mean stealing away without anyone's knowledge, to tie the knot?

What do social mores call for in such instances? Should I purchase a gift, or should I simply say good luck/best wishes in a return email?

GENTLE READER: Your friend has found a humorous way to distract you from the fact that she is not inviting you or anyone else to her wedding. That she did so without adding gift registry information warms Miss Manners' heart. Send a present if you like, but do write, wishing her well and promising not to tip off her parents.

DEAR MISS MANNERS: I have exchanged birthday cards with a dear friend for 20-plus years. This year she texted and Facebooked, but NO card.

I am greatly offended and hurt. Is this acceptable in this age of technology?

GENTLE READER: To be offended at someone's congratulating you on your birthday in an informal manner? Miss Manners considers that taking insult where none was intended is churlish.

DEAR MISS MANNERS: If I want to receive only money for my wedding and no gifts, how can I word it?

GENTLE READER: "Stick 'em up"?

Despite their combined efforts, modernity, convenience and plain greed have not succeeded in convincing Miss Manners -- or most gift-givers -- that both the form and substance of a gift are not at the discretion of the giver.

Before you explain, she hastens to add that she would be unmoved by the justification that you are underpaid, you mean to donate the money to charity, and you loathe your friends' taste.

(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, Universal Uclick, 1130 Walnut St., Kansas City, MO 64106.)

DEAR MISS MANNERS: I feel obligated to help my fellow co-workers' kids when a new fundraising catalogue is brought in to support school and events. I, too, am selling items to help raise money to lessen the financial blow for my daughter's dance class tuition, costumes, etc.

However, I can't exactly afford to keep buying things from co-workers who are also selling things. But I feel it'd be rude not to, especially since I am asking them to do the same for me. What would be the proper etiquette for dealing with this?

GENTLE READER: As you have experienced, embarrassment is an important component in this method of raising money. The idea is to use social connections to pressure people into buying things they may not otherwise want, or even that they cannot afford.

Miss Manners is aware of the urgency with which extra sources of money are needed in the school system. But using schoolchildren to cause this embarrassment teaches them a bad lesson. It is different from the old method, when they were expected to provide a service -- typically, car-washing or baking -- that could make them proud of their ability to earn and contribute.

Your situation seems particularly odd, as your buying from those to whom you sell would make all that effort financially futile.

Miss Manners suggests that you work, instead, on devising a dignified way for the children to earn money. Her guess is that organizing them to help adults learn how to use their computers and smartphones would reap a small fortune. You may then, in good conscience, decline to participate in reciprocal, embarrassing buying.

DEAR MISS MANNERS: I found out earlier this week that my brother was finally marrying his longtime girlfriend in a state 2,500 miles away. They were holding a "housewarming party" where they were going to also have a "surprise" wedding.

My parents happened to be there, and my mother emailed me the information. Over the last 24 hours, she has sent pictures of the "happy event" and clearly expects a response.

Since he didn't have the courtesy to tell me that he was even getting married, I've been ignoring the texts and emails. I'm appalled that he didn't bother to call/email/text me himself about his pending nuptials. Clearly they have been planning the event for a while.

Do I owe the "happy couple" anything? I can't see that I do, but it seems likely that my mother will expect me to do something.

GENTLE READER: It's your brother. Do you really want to break with him over his not having had a big wedding with advance notice?

Unlike you, Miss Manners does not imagine that this event was long planned. Her guess is that at most, they were having a housewarming party anyway, and decided that they didn't need to plan a different event for their informal wedding ceremony.

But like your mother, Miss Manners expects you to do something. More specifically, she expects you to congratulate your brother and welcome your new sister-in-law. And to drop those quotation marks around their happiness.

(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, Universal Uclick, 1130 Walnut St., Kansas City, MO 64106.)