DEAR MISS MANNERS: Describe business formal. Describe cocktail.

GENTLE READER: Business formal is behave yourself. Cocktails do not help.

Sorry, but that's the best Miss Manners can do with the proliferation of vague dress codes.

Regional, professional and eccentric differences aside, gentlemen should wear suits to both, ladies should wear dresses, suits or something equivalent (which is to say, clearly not leisure clothes), and, if possible, add a bit of extra dash for cocktail parties.

DEAR MISS MANNERS: I have a friend in her 50s who is just plain rude. She assumes that she is perfectly entitled to tell parents of misbehaving children (total strangers) how their children are out of line; to loudly and longly honk her horn when someone drives in a manner she dislikes; to bang on her apartment ceiling, walls and floor with a rubber mallet when her neighbors are too loud, etc.

She's nice in private, but in public, she's embarrassing due to her rudeness, which can come out at any time -- most recently when she thought someone had cut in line in front of her and she loudly said, "That's OK. I'm invisible here."

I've tried to gently tell her that "two wrongs don't make a right," but she just brushes me off with, "Yes, Mom." Should I move on, or is there a nice way to let her know the way she treats people is embarrassing and rude?

GENTLE READER: No doubt your friend believes that she is serving the cause of manners by further inflaming people who are already behaving questionably and, incidentally, by ridiculing your embarrassment. That rudeness does not teach the importance of etiquette does not seem to discourage anyone from trying.

Miss Manners cannot authorize your committing the rudeness of criticizing your friend's behavior. But she can suggest that you discuss the matter calmly, when your friend is on her "nice" behavior, by engaging her on the subject of the reactions she encounters.

Is the neighbor more cooperative after those bangings? Do parents thank her for pointing out that their children are misbehaving, and are they presumably open to teaching them better behavior? Do those who cut into line apologize when she denounces them?

Miss Manners is guessing that this will lead to the admission that maybe her outbursts don't change others, but they make her feel better. You will then have to be gentle when you ask what she believes are the motives of others for their rudeness.

DEAR MISS MANNERS: I've been invited to a dinner party. Recently widowed, I am not certain that I will be in a comfortable position and am considering declining the invitation.

Would it be proper for another invited guest to tell the host of my dilemma? Isn't it my responsibility to speak with the host?

GENTLE READER: If you are in the first throes of widowhood, you may ask a friend or relative to explain this to your host. After that, yes, it is up to you.

But Miss Manners hopes that -- firsthand or secondhand -- you will do this in a way that does not suggest perpetual seclusion, making clear that you appreciate the invitation but are in mourning and will be in touch. It is sadly common for widows to find themselves in social isolation after the initial wave of sympathy.

(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: What is your opinion of teaching etiquette in public schools?

GENTLE READER: That teachers have quite enough to do without being expected to do the most basic job of parents.

Teachers generally do have to teach etiquette, because parents often do not, and mastering it is necessary before one can learn anything else. This includes such basics as sitting still, respecting authority and refraining from annoying others. What the homes are like where parents have failed to teach this, Miss Manners shudders to think.

DEAR MISS MANNERS: My adult son (29 years old) is an aspiring rock musician. The son of my old friend is a successful independent rock musician. My son would like to ask my friend's son to listen to his CD containing his original songs.

I want to stay out of it, and I've told my son I would be uncomfortable asking the rock star's mom to intervene. I've suggested that my son write to my friend or to her rock star son c/o her address with his request and include a copy of his CD. What is the right way to do this, if there is a right way? Should I get involved?

GENTLE READER: Staying out of it sounds like an excellent idea. You wouldn't care to factor into your friendship the possible effect of the rock star's ignoring the request or disliking the CD.

Miss Manners guesses that your son's only hope is to send the CD to the mother with a letter expressing his admiration of her son and his wish that she will pass it along as gratitude for her son's music and for the friendship of their mothers. (A bit smarmy, yes, but the idea is to make the mother feel she must do this for her friend, which a bald request would be unlikely to accomplish.)

DEAR MISS MANNERS: Where I live, it is both legal and necessary for cyclists to ride on the sidewalk. If I want to pass a pedestrian who is walking in the middle of the sidewalk, what is the best way to notify that person that I would like him or her to step to the side for a moment?

If I ring the bell on my bicycle, they almost always hear me, but I feel rude dinging at someone. On the other hand, if I say "Excuse me," they almost never hear until I am practically shouting, which does not feel any less rude than ringing my bell.

This problem is exacerbated by the fact that about 75 percent of the people I pass on the sidewalk are walking while occupied with their phones and paying little attention to anything else.

GENTLE READER: This may be the only chance Miss Manners ever gets to correct someone for being too fastidious in worrying about what might be rude.

The purpose of the bicycle bell is not to chastise pedestrians who are on the telephone, or not in the habit of looking back to see what might be coming. Its purpose is to warn people of the danger of an approaching bicycle that may not be able to stop quickly. Use 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, Universal Uclick, 1130 Walnut St., Kansas City, MO 64106.)

DEAR MISS MANNERS: My sister and I are having an argument. She says that saying "please" at the dinner table is begging. If someone wants something, they should just ask and it should be given.

Some of this stems from an abusive father who would taunt people at the table and insisted on "please" and "thank you" and then, after the taunting, would say no or just ignore you.

I can in some ways see her point, but I do not consider it begging. Her children are grown, with children of their own, and all of these kids are now the same way. Even if you do give them something, they never say thank you.

I say that manners are what separate us from animals. They are a form of respect. She says they're just insincere and phony and should not be encouraged.

Am I just too old school? Is it really important? I think it is, and this will hurt the kids in the future.

GENTLE READER: It is only important if you don't believe that those to whom your sister and her family keep issuing orders and ignoring presents will love and admire them for their sincerity.

No doubt your sister is right that she does not sincerely feel respect or gratitude, even to people who do her favors or give her presents. But as she should realize from her father's cruel behavior, even such minor favors as passing the salt need not be granted. Why she would want to emulate him, Miss Manners cannot fathom.

DEAR MISS MANNERS: Although I am of the conviction that marriage is the lifelong union of a man and woman, I am blessed with wonderful friendships with people who do not share such convictions, including two women who consider themselves (but are not legally) a married couple.

I would like to invite both to my wedding, but I am concerned about how to address their invitation(s). I am concerned that they would take offense if I were to send two separate invitations to the same address, one for each friend.

But I don't wish to address them as I would a married couple, because I feel that would violate my own beliefs. Is there a polite way for me to hold to my convictions without causing offense?

GENTLE READER: The etiquette problem that troubles you does not exist. Any two grown-ups, whatever their relationship, who live at the same address but have different surnames may be sent one invitation, which is addressed by using two lines for their respective names.

What troubles Miss Manners is a deeper problem: that in celebrating your own union, you want to make it clear that you do not recognize your friends'.

DEAR MISS MANNERS: Why do reporters and police officers, when speaking of a crime, refer to the perpetrator as a gentleman, as in, "The gentleman is suspected of having murdered his wife and dumped her body in the river"?

GENTLE READER: Probably not for the same reason that Miss Manners calls everyone a lady or a gentleman -- to encourage them to behave as such. Possibly out of a Damon Runyonesque sense of humor. Perhaps because, as Miss Manners must remind you, a suspect is not necessarily a perpetrator.

(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.)