The revival of the junior high school dance is, in Miss Manners' opinion, a boon to the social development of young adolescents. In no other way can they obtain those deep emotional scars that make people so interesting later in life.

The true cruelties of the young people's dance cannot flourish in the setting of the old-fashioned and fashionable dancing class, where a thin veneer of civllization is maintained through the vigilance of presiding adults. In the less formal school dance, the police work of the adults does not usually get into the jurisdiction of social niceties.

Therefore, the conscientious parent must do some advance work on the child for his or her own protection. Too often, modern parents assume that their children are too sophisticated to require such guidance. But even years of pornographic research do nothing to equip an unsuspecting child for the frenzied experience of attending his first school dance.

This preparation may or may not include learning how to dance. This is a frill item. What the children need is a quick course in sexual-emotional history.

Dear child (each must be told), you are about to experience astirring of feelings toward a member of the opposite sex that is universal and natural. What it is, is a desire to be looked down upon by someone whom you feel is better than you are, coupled with a more generalized desire to look down upon people whom you feel are worse off than you are.

Dear child (you must continue), you cannot avoid these feelings, but you must learn to disguise them in order to avoid jeopardizing your present and future social life, and therefore creating for yourself even more agony than is already built into the situation.

At a school dance, this works as follows. Two or three children in the crowd exhibit, either from cleverness or accident, an air of self-confidence not normally linked to their age group. All the other girls then fall promptly in love with the boy who has this air, and all of the other boys fall in love with the girl who does. Just as automatically, they all decide that they despise all the other members of the opposite sex.

(Many people go through life falling in love on this law, which by definition guarantees unhappiness, but everyone starts out that way. There is no such thing as a 13-year-old whose affections have been aroused by the charm of vulnerability.)

The result is that there will be a great deal of slighting going on at this dance, both blatant and in an off-hand fashion, as the children make clear their unwillingness to settle for anyone less than the unobtainable ideal. Boys will be heard loudly explaining why they will not ask certain girls to dance, and girls will make public refusals to certain boys who do make that effort.

Dear child (you must continue the lesson), let me tell you something you will have great difficulty in believing. If you indulge in this behavior, it will come back to haunt you. But if you overcome your natural distaste for those of your own level of popularity -- or lack of it -- you will reap the reward later.

The reason is that while it is extremely common for the desirability of a person to change radically after his early adolescence -- sometimes during it, from one year to the next -- everyone goes through life with a vivid memory of insults and kindnesses (if any) experienced at those first dances.

The popular boy or girl for whom you lusted from afar may live to bore you silly, which is an excellent reason against early marriage, but the beautiful creature you slighted when she had pimples or he stuttered will be only too pleased to break your heart for you when it gets big.

And tha, dear children, is why we must learn to be polite to others.

MISS MANNERS RESPONDS

Q. I brought two nice gifts from Europe (value about $30) for a friend who house-sat for us in our absence. My return and presentation of the gifts coincided with her decision to move to another city, and she left them on our living room coffee table. Even though she visited the house four more times, the largish items remained in the place where she left them and she never said work one. She has now moved away. I don't really feel like storing them for her until she remembers them a year or so from now -- if she does.

A. Perhaps your house-sitter has come to feel that your house is a second home to her. This sentiment should be discouraged. As you are not obligated to give the same present more than once to the same person, you might present them to someone else and cultivate a confused look in case she ever asks you for them.

Q. What am I supposed to say when I am introduced to a homosexual "couple"?

A. "How do you do?" "How do you do?"

Q: Does a formal bridal portrait have to be just of the bride alone? I have seen some, with announcements and in people's houses, that show the couple in a formal pose -- I'm not talding about the condids of her feeding him wedding cake, or anything like that -- instead of just the bride in her wedding dress and it seems to me that it makes much more sense. After all, they're both getting married, aren't they?

A: It is true that many modern couples have the notion that the bridegroom is as essential an ingredient of the formal wedding as the bride. Miss Manners wouldn't mind this so much in matters such as photography if she didn't know where this kind of thing leads. It leads to husbands thinking that they have as much right as wives to play starring roles in the delivery room -- that's where it leads.

Q: What do you think of sending thank-you notes to hosts after a 3-year-old's birthday party? It seems to me an exaggeration of a social convention, vulgar because it is inappropriate.

A: Inappropriate, but not vulgar. The appropriate letter for the parents of a 3-year-old to write to people who have been his hosts at a party of small children is an apoligy.

Q: What is the difference between a gentleman's top hat, and an opera hat?

A: The opera hat, like some gentlemen Miss Manners has observed at the opera, collapses.

Q: My wife and I went out to dinner last night with a couple who are close friends -- it was just the four of us, and most of the evening was quite pleasant. But there were several periods when both of our friends were absent from the room we were in -- first, when they were running in and out of the kitchen, getting ready for dinner, and later, when they both cleared the table and when they both went upstairs at the same time to say goodnight to their children.

What in the world are my wife and I supposed to do alone together while they're a way? That doesn't sound right -- I don't mean that my wife and I have nothing to do with each other or nothing to talk about. What I mean is that neither of us felt like talking over the details of the day -- the kind of conversation we would have had at home -- knowing that they might pop back in the room when she was talking about the bills or I was talking office gossip.And yet we don't want to sit there like dummies so they think we're bored with each other.

A: Every couple should have a topic ready for such situations. The best ones are extremely distant -- "How should we do over the house when the children are grown?" "What would be good second careers for us if we went back to school after retirement?" -- because they are generally more graceful than discussion of recent situations, such as, "Did you pick up the things I asked you to on the way home?"

Q: Is it true that the guest of honor must leave a party first because no one else is supposed to depart before that? It seems unfair. When a party is in your honor, you are likely to be having a better time.

A: This is exactly why one must allow others to go home. Besides, being honored is enjoyment enough for one evening -- you mustn't force people to allow you to be charming, as well.

Q: For several years now, I have occupied a succession of high-rise apartments, and in each of them this problem of mine has come up. Specifically, what is the correct attire for those little impromptu social hours under the lobby chandeliers during a fire in the trash chute? These occasions invariably occur well after midnight, so that one leaps from one's bed to attend the festive gathering.

My personal feeling is that one's dress should be adequately covering but informal. I generally wear a navy blue nylon pajama and matching coat, tennis shoes, and carry a bath towel of contrasting color as my sole accessory: when I was in college 50 years ago, we were required to carry bath towels to fire drills, to wrap around our noses in case of smoke.

Last time, I spent an agreeable hour chatting with 1) a young man clad in running shoes; 2) an executive type in a business suit with vest, carrying a briefcase; 3) a young lady in a scarlet caftan, her head swathed in a brilliant yellow towel. Her accessory was a brown grocery bag that contained a live cat.

A: Your instincts are correct, but, then, so are everyone else's, as fires are classified socially with come-as-you-are parties. However, Miss Manners' instinct would be to avoid the man in the three-piece suit. A person carrying a briefcase at midnight is up to no good.

Feeling incorrect? Address your etiquette questions (in black or blueblack ink on white writing paper) to Miss Manners, in care of The Washington Post