DEAR MISS MANNERS: Is dining etiquette different when on an airplane? Should I wait for everyone in my row to be served before eating, as though they are my dinner companions, or should we all politely ignore each other?

What other rules can be ignored, or should be amended, when drinking or eating on an airplane?

GENTLE READER: There are many courtesies that you owe your seatmates on a flight, but pretending that you are at a social event is not one of them. If it were, it would be rude to fall asleep while the others were awake.

The fiction that should be observed is that you are each enclosed in your own space, however sparse that is. Therefore the dining rules require not intruding on others’ space with spills or smells.

DEAR MISS MANNERS: My wife, son and I have been invited to my sister’s club for pasta/pizza buffets for the past few years, and always have a great time. This year, my son, after having made a few trips through the buffet line, got himself some dessert (ice cream with toppings) from the dessert table while everyone else was still having entrees.

Nothing was said at the time, but on the way home, my wife informed him that he should’ve waited for everyone to have finished their entrees before getting dessert. I disagreed with her, saying it was OK to eat at his own pace.

GENTLE READER: Apparently your wife wants to teach your son how to be a guest at a communal meal, to which others have kindly invited him. You, in contrast, seem to believe that the manners for eating alone will be enough to carry him through. Miss Manners considers that your wife’s approach is more considerate, not only of the other guests, but of your son.

DEAR MISS MANNERS: I have lung cancer, even though I never smoked. My prognosis is not good; basically I’m on treatment to just extend my life, but it can’t cure me. People who know I have lung cancer see me out on my infrequent public outings and always say, “You look great.”

What should be my reaction? Yes, I look good. But I have been told by doctors I may have a year, maybe two. I’m disabled, can’t taste food, get out of breath if I walk more than a block without resting, etc., due to the cancer and its treatment.

What do I say, and why do people base everything on how I look?

GENTLE READER: Would you prefer their saying, “Considering that you’re on your last legs, you look pretty good”?

Miss Manners can sympathize with your being raw about any comments about your tragic state, but there is no cause to blame people who are only trying to say something nice -- and apparently true, as you acknowledge that you do look good.

Your response should be a mere “Thank you.”

DEAR MISS MANNERS: What does one say to a person who gives unasked-for advice or pseudo-compliments, without being equally rude in return? Others must have this problem and dread events as much as I do because of it.

GENTLE READER: “How kind of you to take an interest in my personal affairs.”

(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: Several times, friends, acquaintances and family members have apologized to me (face to face) for their not having written a sympathy or thank-you note.

I did not know how to respond to, for example, “I heard that your father died, and I should have sent you a note, but I didn’t and now I feel bad about it.”

I’m afraid I said something like, “Yes, there was lots of sorrow all around,” but I really feel doubly offended.

And many times I have heard, “I loved the (party, lunch, gift) you gave, and I should have sent you a thank-you note.” How would Miss Manners respond?

GENTLE READER: “That’s quite all right. I didn’t expect it.”

Miss Manners is not sure that the All About Me Folks -- you lost your father, and therefore they want you to console them -- will understand. But it should make you feel better.

DEAR MISS MANNERS: Is it appropriate for a mother-to-be to send thank-you cards for the baby shower gifts?

GENTLE READER: Unless the baby is going to do it. Or the father-to-be, which may be even less likely.

DEAR MISS MANNERS: I am the matron of honor in my sister’s upcoming wedding. My husband is also in the bridal party as a groomsman.

As is customary, my sister is planning to have the bridal party share a first dance, each attendant with their partner. My mother is insisting that, as matron of honor, I must dance the first dance with the best man, and likewise, that my husband should dance with his corresponding attendant.

Personally, I’d rather share the first dance with my husband, since he’s also in the wedding party, and I will be several months pregnant with a sizable baby bump at the time (read: awkward for dancing).

Does wedding etiquette dictate that the maid/matron of honor and best man MUST share the first dance together? I will be exiting the church and entering the reception with the best man. And of course, I’m happy to do whatever my sister wants. But I’d appreciate your advice on the formal etiquette.

GENTLE READER: You would be shocked to know how little etiquette cares who dances with whom.

While it is customary to have the bridal couple dance first together and then with their parents, the hope is that this leads to the guests’ doing so, rather than an exhibition for them to watch. It is useful to have the bridal party take to the dance floor to encourage others.

What your sister is suggesting is an orderly pairing, not a romantic one. Miss Manners would not object to your dancing with your husband, but neither does she see this as precluding your doing so for the rest of the evening.

As for the baby bump, that is rather charming at a wedding. In any case, it will maintain your distance from your non-husband, if you think that necessary.

(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 hired a tradesperson to do some painting and odd jobs on my property. As we were discussing the bill, he said “You can either pay me, or take me to dinner.” I was so shocked that I immediately changed the subject and asked him about a piece of leaky guttering that was concerning me.

Putting aside the fact that I felt his behavior was inappropriate and unprofessional, I am an asexual woman with no interest in romantic relationships, so any such invitation will need to be declined. Could you please equip me with a phrase or two that I could use in the future, and advise me how I could have handled the above situation better?

GENTLE READER: While Miss Manners finds her interest piqued by your explanation, she assures you that it is unnecessary in declining unwanted invitations.

You may simply say “Thank you, but I am afraid that is out of the question.” That you do not date, and why, will only invite more unwanted attention.

However, there is a significant difference between declining an invitation in a social situation than in a professional one. In the latter, you may be dependent on the person’s work, or otherwise required to have another encounter. In that case, you may say, “I am sure that your boss (or union, etc.) would not want to collect their fees in dinner. Let us keep this relationship professional” --doing your best not to make it sound, at least overtly, like a threat.

DEAR MISS MANNERS: I am a social media user, and would appreciate a list of DO’s and DON’T’s for polite social media use in society. I am also a young professional, and would like to keep interactions with work colleagues appropriate, as well as those with old friends and family.

My children have interestingly asked me to not post so many photos of them, or to ask them first. I have thought about deleting my account, but appreciate the ability to stay in touch with people important to me.

GENTLE READER: DO NOT post pictures of people without their permission -- or of yourself, if you are not certain that there won’t be professional repercussions.

DO get separate social and business accounts if you are unable to perform the above.

DO NOT use “likes” to check your self-worth and the status of your friendships.

DO NOT post deeply personal things and then act shocked when your friends make reference to them.

DO NOT assume that any invitations sent on social media are binding. Or be surprised when either no one shows up -- or overcrowding necessitates that the police do.

DO NOT use Social Media as a platform to disparage your friends, family or co-workers, even if you think you are doing so in vague terms. They will know.

DO stay in touch with people who are important to you through means other than social media. Miss Manners herself has enjoyed a long and healthy social life without it, and plans to continue doing so.

(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.)