DEAR MISS MANNERS: I use text messages to ask and answer specific questions or to relay information. For conversations, I use telephone calls.

A former graduate student recently contacted me via text message, and I was really enjoying catching up. If we had been conversing via phone, I would have known the cues that indicated whether and when she wanted/needed to wind the conversation down.

Being in the dark about the conventions of messaging, I asked her to let me know when I was carrying the "conversation" overlong. Then I asked her a few more questions about her life to let her know that I wasn't hinting that I needed to end our chat.

She didn't respond. At all. Could you advise me if I need to do something differently in the future?

GENTLE READER: There is a tendency to think that new technology requires entirely new etiquette, when the truth is more incremental.

The telephone conditioned us to provide verbal cues ("I'm so sorry, but I really have to go") to replace the nonverbal ones (anxious, furtive glances at the clock).

The biggest etiquette consequence of texting derives from its immediacy: Conversations can have lacunae when, unbeknownst to the other party, the train arrives at the station or the doorbell rings. One could offer to "be right back," but it is also permitted to suspend the conversation for later resumption.

None of which requires a modification of your behavior -- though your student, if she had no intention of returning to the conversation, should have indicated that she was signing off.

DEAR MISS MANNERS: I heard a funny story from a friend who took another friend out for dinner at a nice but casual French restaurant. The friend found a hair as she was diving into her roasted chicken dish.

Having alerted the waitress, she was offered a profuse apology, assured the meal would not be put on the bill and asked how long she would be willing to wait for a new dish. The friend thanked the waitress and said that no new dish was required.

When the waitress had retreated, she then turned to my friend and said, "Is it OK to eat it or not?" She did eat it, and loved it.

Now I am curious to find out what the correct response would have been. Can you help me?

GENTLE READER: Your friend's friend's manners, as well as her dinner, are in need of a trim.

Warning the staff that the food is contaminated is, to a reputable restaurant, only slightly less worrisome than screaming "fire!" -- it is equally likely to empty the dining room, albeit on a different time scale. Neither the staff nor the fellow diners would find much comfort in subsequent assurances that it is only a small fire.

Even if she was not squeamish about the chicken, she should have considered the impact on others by informing the staff quietly and setting the dish aside. As to your friend's options, Miss Manners believes only one remained: looking green and asking to be excused for not feeling hungry.

(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, Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106.)

DEAR MISS MANNERS: I always sent a Mother's Day card to my dear mother, who has since passed away. I also acknowledged any close motherly relatives.

My three children are grown with children of their own. However, my one daughter seems to think that I should give her a card, whereas I think her own children should have that filial duty when they are old enough to understand. (I am also of the opinion that the greeting card industry encourages extra card-sending for its own benefit.)

GENTLE READER: It was Miss Manners' own dear mother who declared Mother's Day to be a mistaken notion. "It implies that there are 364 days on which children do not have to show their love and appreciation for their mothers," she would say.

Yet she also taught kindness, which makes it difficult to oppose the spread of Mother's Day beyond mothers and mother-figures. But yes: It seems ridiculous and self-centered for a child to demand such acknowledgment from her mother.

Perhaps you can find a gentle way to point out that your daughter is going in the wrong direction: "You're not my mother, dear; I'm yours."

DEAR MISS MANNERS: I work at a grocery where customers are constantly startling me or becoming angry at me. I have noticed that customers do not know how to make their presence known.

If they approach from out of my line of vision, many will tap my shoulder or grab my wrist, causing me to scream. Others come alongside me and begin talking. While I may hear them, I assume they are on their phone. It may take a few seconds for me to catch a couple of words that make me aware they need my help.

When I am on a ladder stocking upper shelves, customers knock into my ladder trying to squeeze a 19-inch cart through a 15-inch opening. Others prefer to reach under and around me to get to an item they want.

After I have screamed in surprise, I usually turn to them, smile and say, "Please let me know if am in your way. I will happily move."

Most of them say they did not want to bother me -- without realizing that scaring me is bothering me. A few try to blame me: "You shouldn't be doing that now."

Others look at me and say they didn't hit me with the cart. One time I was jostled hard enough that I had to grab the shelf in front of me, knocking boxes off. A box hit the customer on the shoulder and she told me I needed to be more careful.

I never raise my voice. I smile. On very rare occasions, I have looked at someone and said, "I am sorry for being so clumsy. I really do not want to find out how good my insurance coverage is."

GENTLE READER: You must be the only polite person to be found in a grocery store these days. Miss Manners keeps getting mail about altercations taking place in the aisles or checkout lines. The standard is so low that someone wanted credit for not hitting you with a cart.

Where is a peace-loving citizen supposed to get vittles in safety?

It is to be hoped that your customers are learning, one by one, from your screams and explanations. Miss Manners is sorry you have to put up with their thoughtlessness.

(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, Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106.)

DEAR MISS MANNERS: As a gift for a friend whose birthday is coming up, I have offered a complimentary stay at a condo I own in a beautiful, remote area. I could also watch her child during the trip, as our kids are the same age. Alternatively, the gift could be an outing on our boat.

Today, unprompted, she suggested I get her a facial at her preferred provider in town. I was a bit taken aback, and thought perhaps I misheard her.

I could understand if we had been discussing possible gifts at the time, but the suggestion out of nowhere seems presumptuous. Thoughts?

GENTLE READER: Yes, it is presumptuous. But we have developed a culture of allowing people to choose their own presents. Gift registries are so common now that the very idea of deferring to the donors' ideas is deemed naive.

What if you are given something you don't particularly want? Worse -- what if you therefore missed the opportunity to get other people to buy you what you do want? Miss Manners finds this attitude toward the expected generosity of others to be unseemly, but it is the premise on which your friend's suggestion is based.

In all fairness, your offer of the condominium would involve extensive planning on her part. She could have thanked you and said that unfortunately, it was not possible for her to get away to enjoy your kind offer. Then you could have made another suggestion, or even asked her what she might like.

Instead, she took it upon herself to assume your function of deciding what to give her.

Does anyone stop to think how callous and pointless all this makes the entire concept of giving and receiving presents?

Cynics sneer at the adage, "It's the thought that counts," thinking it hypocritical, when what really counts is getting stuff for free. Or better yet, eliminating the danger of disappointment (to the recipient) and the nuisance of thinking (to the giver) entirely by substituting money for objects.

Thoughtfulness is flattering because it means that someone has noticed what you like, and cares to indulge you. When it works, it is a thrill to receive something wonderful that you may not have known you wanted -- from someone you realize really understands you.

Granted, that may be rare. Those with good intentions may misjudge or not know the recipient well enough. Those with indifferent intentions find it easier to be told how to pay what they seem to owe.

That is why we allow a system of hinting and checking with third parties. But if people are going to outright choose their own presents, they might as well do their own shopping with the time and money they might have spent meeting the demands of others.

DEAR MISS MANNERS: My teenage son blows his nose, loudly, in the shower. I maintain that it's gross, and say he should use a tissue either before or after his shower. My husband says there's nothing wrong with it.

I don't want my son to unintentionally disgust others. What is your ruling on this?

GENTLE READER: That you should not be hanging around the bathroom while your teenaged son is taking a shower. Nor speculating about who might someday shower with him.

(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, Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106.)