WOULD YOU mind toning down the hospitality just a bit? Thank you. Although Miss Manners is not opposed to a bit of tasteful merriment at this time of year (and on alternate Saturdays), she believes that less pressing conviviality would enable us all to have a better time.

A gracious host must be able to take no, or at least no, thank you, for an answer. And if he takes it, he should also be able to dish it out.

Let us take, for example, the first possible no, the one delivered immediately after the invitation is issued. Upon hearing it, the gracious host says, "I'm so sorry; another time." He does not say, "Why don't you drop in afterwards" or before, or between courses of the dinner being pleaded as a previous engagement.

If the invitation is accepted, however, the host has a good chance of saying no to the ubiquitous question, "Can I bring someone?" and the less heard, and perhaps less sincere one, "Can I bring something?"

One can always say yes, of course, if one feels that a peach cobbler, or Peaches herself, would add to the festivity. But it is perfectly proper to decline these offers. Miss Manners herself, under these circumstances, declines extra guests with the excuse, "I'm so sorry, I only have 10 forks." This is the literal truth, if one understands it to mean that she has only 10 each of oyster forks, fish forks, luncheon forks, dinner forks, salad forks, fruit forks and dessert forks.

When a guest arrives, and is offered a drink, the host must take no -- or "club soda, please," which some people consider the equivalent of no -- for an answer. There is no polite way of arguing with a guest's choice of drink or decision not to drink.

This is also true of food. When a guest declines a particular food, or leaves it untouched on his plate, or declines a second portion of what he has apparently enjoyed on the first round, no comment is appropriate on the part of the host. Arguments that something is particularly good, rare, non-fattening, home-grown, cooked expressly in the guest's honor, or otherwise fated to make an unwelcome appearance at the host's breakfast table or an ignominious one down the garbage disposal, are inappropriate.

In fact, there is altogether too much discussion of food quality and preferences at the dinner table these days. Please cut it out.

During and after dinner, the host should feel free to say no to unwelcome offers of help. Again, one may accept if one wishes, but the statement, "Thank you, I prefer to do it myself" should be repeated until it is obeyed.

Then there is the matter of the guest's announcement that he had better go home now. This is not, as many hosts believe, a negative statement, but rather a positive one of having had a perfect evening and not wishing to risk spoiling it. Nevertheless, many people take it as a challenge, determined that no one, however tedious, should be allowed out the door without a fight.

The answer to "I must go," is not as many suppose, "Must you -- do have another drink, it's early," but "I'm so glad you could come."

Perhaps somewhere in the world there are hospitable people whose hearts are broken when, after their having taken the trouble to prepare and carry out a flawless party, they discover that their guests nevertheless plan to return to their own dwellings in good time for the next meal. Miss Manners has yet to meet one.

MISS MANNERS RESPONDS

Q: I enjoy presenting books to friends and relatives for holidays and personal occasions. It would be a great boon to me if you would discuss the etiquette of books as gifts. Two points that are especially troubling me are, first, is it correct to remove the price, or is this an unnecessary mutilation, and, second, is it proper to write a presentation note in the front of the book in all cases, some cases, or is this yet another mutilation of the volume?

A: You have come to the right respecter of books. Miss Manners' reverence for such objects is so great that it prevented her in college from underlining the one sentence that summarized each book and thus almost prevented her from working her way out of college.

Nevertheless, one must exercise some judgment, she has concluded with the advent of fussiness brought on by age and by shrinking shelf space. One should never permit bores or trashy or trivial people to share one's living space, even if they come in the respectable guise of hard covers.

She points this out, not only to establish her credentials, but to encourage tolerance in you for those of your friends who may wish discreetly to exchange or donate to charity books you have given them. Naturally, it is less likely to be a matter of taste than of duplication. In every case, it is one of the great virtues of books as presents that they may easily be disposed of.

Snipping the price out does not interfere with their exchangeability, and books are no exception to the rule that all presents must have their prices removed.

Before you write in a book, however, you should be quite certain that the person will appreciate it enough to keep it, but not so much as to have already purchased it. When in doubt, put your sentiments on a card, rather than a fly leaf.

If you are the author of a book, by all means autograph it to increase its value and preserve it from the outrage of being exchanged.

Q: Two friends of mine have husbands in the restaurant chain business. On occasion, one couple may invite my husband and me out to dinner at one restaurant at no expense to us, or to them, I might add. Or my girlfriend may invite me to lunch, with again no cost to either of us. How should I reciprocate under these circumstances? To take them out, our expense would be great, or even a home-cooked meal would be of considerably more time and expense than they put out. Is the obligation a meal for a meal, or should finances enter in? Should I cook one meal for each two of theirs? Or should this benefit of theirs be considered just that, and I return the gesture at my own expense?

A: Well, let's see. The formula is that you add up the wholesale, not retail, cost of each item of food you consumed, figure in the amount of labor required by cook, waiter and dishwasher, and then add 15 percent for the degree of friendship, taking care to make it 20 percent during the holiday season. Make that your budget for any meal to which you invite them. If they should overstep your limit, for example, eating two mints after dinner instead of one, you may apply that to the cost of your next meal.

What kind of friendship do you have with these people? What kind of attitude do you, and possibly they, have in counting whatever comes out of a business as being free of cost to anyone?

The only applicable social formula of which Miss Manners knows is that each party to a friendship should initiate approximately the same number of occasions spent together. If money is a factor, you are not talking about friendship.

Q: I find myself faced with a dilemma regarding the etiquette of gift giving. My brother is living with, but not quite married to, a woman who is more than a roommate but less than a wife, which is to say she shares bills, board and bed, without the benefit of legal sanction. Henceforth she will be referred to as his convivant, for lack of a better term.

My relationship to this convivant and hence my social obligations to her are not clear to me. What is an appropriate Christmas gift for a person who is neither in nor out of the family, related by neither blood nor marriage, but living among us in an intimate yet ill-defined manner nevertheless? Is any gift at all required, or even wise? I do so want to do the proper thing.

A: You have no idea what satisfaction it gives Miss Manners to know that in these interesting and trying times people such as you are out there determined to do the proper thing. Merry Christmas to you, and may your New Year be filled with propriety.

Do not, repeat not, give this woman your great-grandmother's pearls. If she and your brother are not willing to commit themselves to a permanent bond, there is no reason why you should make a commitment you will regret if their relationship is dissolved.

Otherwise, Miss Manners sees no reason why you should not give a present to a member of your brother's household, and would consider it obligatory if she comes to the family Christmas celebration. If one withheld such privileges until any attachments, including the legal, were proven permanent, the stores would be empty right now.