"DO I have to wear my leggings? Nobody else does."

"You know it drives your father crazy to see your hair hanging down like that.''

"You call that dressing up? For what?"

Such remarks, once the perennials of the family garden of tussles, are now rarities. The way to get a child to wear a snowsuit, bib-style leggings and all, is to attach lift tags to the zipper and call it a ski suit. The emotional charge any argument over hair length in children used to produce is no longer possible, because the batteries are too weak. And dressing up, these days, seems to be a custom kept alive only artificially by people who are attending parties given by or for those who design dress-up clothes.

Miss Manners hates to see such venerable topics for disagreement disappear. It seems to her that children and parents need to maintain healthy differences of opinion, just to keep them in good argumentative trim, and that if they have no superficial pretexts, they are in danger of finding fundamental ones.

Here then, in the hope of reviving the struggle, are Miss Manners' basic rules for fighting out that great generational question of Do I Have to Wear That? or, You're Not Going Out Like That!

1. Health considerations. The cause-and-effect relationship between wardrobe and disease is so regularly invoked by adults who believe in punitive medicine ("Of course you have a sore throat--you went out without your mittens last Thursday") that no child gives it the slightest credence. Miss Manners believes parents should have the final say in decreeing what must be worn for health reasons, but that they will obtain this only through subterfuge. The idea is to make the despised item take on the glamor--from an association with sports, the arts (loosely defined to include noise) or sophistication--most valued by the child. Remember, no mother ever died of pneumonia from not putting on her fur coat. Incidentally, the privilege of complaining that a child's clothing will lead directly to illness is a permanent one. Asking one's middle-aged child, "Is that all you wore over here?" is considered a sign of affection.

2. Taste. This is a tricky matter, as our society is unfortunately set up so that young people sometimes get the general fashion news first. You do not want to ban anything you might be wearing next year. The best thing is to permit nothing permanent (such as tattooing) or that cannot be well-concealed (such as a shaved head) and fight the rest of the question out on the grounds in section three.

3. Appropriateness. Clothing being a convention of the society, the argument of wearing what everyone else wears has some validity to it; more, certainly, than in the moral realm, would doing what everyone else is doing. One does want to conform, in a general way, to the prevailing standards. (N.B.: This rule may not be invoked to support purchasing expensive fad items.) And the prevailing standards are different among children than among adults. A sensible compromise is to allow the child to dress, within reason, as do his peers when he is among them, provided he dresses, when among the parents' peers, within their standards of how a child should look for whatever adult occasions the child may be attending.

There. Miss Manners hopes these rules will enable the generations to take up the conflict again in an orderly manner. She really cannot bear the sight of all those families, sitting about in their identical jeans, sneakers and T-shirts, too listless to get into the fray. MISS MANNERS RESPONDS

Q. One of our coworkers is apparently carrying on a liaison with another coworker (of the opposite sex). At least, they are seen together frequently enough that even people who don't know them have begun to comment. Ordinarily, this would be the kind of thing that makes life in the office interesting. In this case, however, the situation is complicated by the fact that the male coworker is married to a close friend of ours and is about to become a father.

Should we say anything, and if so, to whom?

A. Undoubtedly, you are saying a great deal, to one another. "Did you see the way they exchanged glances in the board room?" "Poor Annie, she probably doesn't suspect a thing," "This is the third time this week that neither of them came back from lunch until four-thirty," and so on.

That is about as much office fun to which you coworkers are entitled. To extend it by making a pregnant woman miserable is not nice.

Besides, you don't really know what is going on. They may be plotting a corporate takeover for the purpose of establishing a trust fund for the unborn baby, and the gentleman's wife may be directing it all from the sidelines. The days when you could safely assume that romance was the only possible motivation for a lady and a gentleman to seek each other's society are over.

Miss Manners noticed that you asked her only to whom something might be said--not what should be said. She is unpleasantly curious about what you had in mind. Perhaps, "My, you must be about due. How do you feel? And by the way, do you know that your husband has been running around with someone from the office?" Or, "Do you really think you ought to be carrying on like this?" Observations and questions, indeed, that so many people have thought must add to the general happiness of the world.

Q. I am a diabetic and am on a weight-reduction diet. Recently, my husband and I were invited to a dinner, the likes of which we were unable to refuse. My husband's job was involved.

A number of rich and very caloric dishes were served. I ate enough for me, but I was constantly pressed to eat more. Pressed to the point of rudeness.

My parents brought me up never to discuss illness at table, and so I do not advertise my disease.

After dinner, my host and hostess retired to the library and we were invited to join in with coffee and brandy. I joined with coffee, and was given a very hard stare for refusing brandy. I personally do not like the taste of alcohol, and it is certainly not good for me.

My hostess regaled me with the preparations of the dinner and the disappointment which stems from guests not doing their part to enjoy the meal and hospitality which comes with it.

When we left, I was mortified with shame and the sense of inability of how to cope with social occasions, while still following my diet, which keeps my blood sugar under control.

Please, Miss Manners, how do I deal with this? To tell people to prepare special food just for me is impolite and unthinkable. Yet, to overeat and indulge my hosts is just as unthinkable.

A. You have made only one social error, but that was a big one. It was to be mortified with shame, etc., when you had done nothing wrong and were merely the victim of other people's bad manners.

The point at which pressing people to have food becomes a rudeness is at the starting point. Hospitality consists of offering food, not extolling its wonders and demanding that the guests consume it.

You are doing quite well with your refusal to offer your illness as a buttress to the argument, but perhaps you need a general refresher course in Miss Manners' art of polite refusal. Briefly, it is to continue to repeat "No, thank you," after every urging, no matter how many are made. The difficult part, but the essential one, is to refrain from offering any explanation--in other words, to shut up after those three words, until you are required to say them again.

An additional, optional technique is to accept what is being pressed upon you, and then not to touch it. If pressed for an explanation of that, you merely give them a satisfied smile with just a trace of regret in it, and say, "Oh, thank you, I found I just couldn't." Perhaps after throwing away perfectly good brandy, they will learn.

Q. My husband and I socialize from time to time with a particular couple whose company we both don't enjoy very much. Despite the fact that we never initiate a suggestion for getting together, they unfailingly seek to set up future dates with us. We don't dislike them, nor do we wish them to develop ill feelings toward us. How can we avoid future activities together without unduly hurting them?

A. Has it occurred to you that accepting people's hospitality is not the way to drop them? It is also, incidentally, rude to do so without reciprocating.

The way to drop people is to decline their invitations, politely, individually as they are issued, but consistently. As you will then incur no obligations, you will be legitimately excused from entertaining them. Get it?