Q: The most pressing problem our daughter and her friends face is what to do when your roommate brings a member of the opposite sex into the room and starts making love, pretending to believe that you are asleep.

Both male and female undergraduates are miserable about this, and none of them knows how to handle it. Leaving the premises is not always a practical solution.

My suggestion is to throw open the windows, turn all the lights on, go for the vacuum, and start cleaning the room. I feel the whole problem will then resolve itself very shortly, as I have never known anyone who could make love with the vacuum on.

If the misbehavers say that one has no right to clean one's room or vacuum at 3 a.m., one has the right to say that otherwise, one would be participating in making a voyeur of oneself. (I had to put that in my letter to my daughter, because these young ones can think of nothing at all to say as to why they object.)

I felt that in short order, an arrangement would be made about when the room would be available for such activities -- only by prearrangement. In any case, one would have a cleaner room.

A: Miss Manners really doesn't know, now that you mention it, whether or not anyone she knows is capable of making love with the vacuum running.

But she is so mesmerized with the question, and, even more, by wondering how anyone could possibly have acquired such information about one's acquaintances, that she can hardly focus her attention on the chief problem.

Nevertheless, she is aware that what you describe has become a serious problem in college dormitories. That is what comes, she must say with her severest tsk-tsk tone, of abolishing parietal rules.

Back when coeducational dormitory living began and everyone else was direly predicting moral chaos, Miss Manners was lamenting, "How is a decent girl going to be able to wash her hair?"

The difficulty is, you see, that some of the rules were changed, but not others.

When institutions made romantic privacy rare, it was an unwritten law that anyone who had such an opportunity must be given precedence over the lesser desires of roommates to study, sleep, or just live in their very own rooms.

This law is still mistakenly observed, even though the privation that inspired it has ceased to exist.

Your daughter and her friends should require neither excuses nor spring-cleaning to enjoy the privileges of using their own rooms. They must insist on setting firm rules about when the room may be used for private entertaining, and enforce them by announcing to violators, preferably at the worst possible moments: "Okay -- out! Social hour's over! Everybody who doesn't live here has to go home now!"