DEAR MISS MANNERS: At the grocery store, I was walking down a narrow aisle with my cart, keeping to my side of the aisle. While you could fit two carts passing side by side, it would have been a tight squeeze.

I was two-thirds of the way through when an older woman approached the aisle. She saw me coming, backed up a few steps, and moved aside for me to pass through. I smiled and nodded and continued on, out of her way.

As I passed, she irately yelled, “YOU’RE WELCOME!!!” at my back. Reflexively, I turned and said “Thank you,” but as I walked away, chastising myself for being rude, I began to question who was in the wrong in this scenario.

I had the right of way, since I was already in the aisle; I didn’t need or ask her to step aside, as we both could have fit through; stepping aside and waiting was her preference, and I obliged her by quickly getting out of her way so she could proceed comfortably.

Doesn’t she, in fact, owe me a “thank you,” if one is owed at all? Also, wouldn’t my smile and nod have sufficed in a situation of mutual convenience?

Miss Manners, I pride myself on etiquette and manners, and this situation has been eating at me for far longer than it’s worth.

GENTLE READER: To thank is polite; to demand thanks is rude. Miss Manners therefore declares that this etiquette competition is nullified. But she wonders why you would want to pursue the opponent’s way of thinking.

DEAR MISS MANNERS: I have always been generous with tips, particularly to restaurant servers. As a teenager, I would bring my baby-sitting money to sneak onto the table and supplement the somewhat miserly tips left by my father. (He insisted then, and still does, that 5 percent is acceptable and 10 percent is generous.)

Now, as an adult in her 30s, I tend to tip over the standard. Unless there was an issue with the server, I typically tip 30 percent. I understand that I give more than the typical amount, and have no issue with those who give less.

I run into trouble, however, when out to dinner with other people. My dining partners almost always ask, “What are you tipping?” and lean over the table to look at the ticket I am completing.

When I respond honestly, they act either embarrassed or upset (for tipping less) or they lecture me for the amount of my tip. When I refuse to answer, they seem suspicious.

What is the best way to respond to the question, “What are you tipping?”

GENTLE READER: “A cow and three chickens. How about you?”

Demanding disclosure of financial decisions is not polite. Miss Manners recommends that you reply to those seeking it, “Oh, I probably overdo it, but I know what it’s like to have student loans and fast food for dinner.”

And for any companions you suspect need more specific help, you might add, “Can you believe that my father used to think that 10 percent was generous?”

(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: A while back, I needed a bed for emergency housing for a long-term houseguest. A friend of mine offered to let me borrow an extra box spring and mattress. (I offered to pay her for the rental, but she refused.)

The guest came for three months of medical care and then went home. The mattress was in the same condition as when it arrived in my home.

When I called my friend to make arrangements to return her bed so that I could have my living room back, her response was, “That’s OK. You can just hang on to them.”

This went on for six months. I would call her and thank her for the borrow, again, offer her money and explain that I wanted my living room back. She would insist that she was fine with the current arrangement.

So, the last call I made, I asked her to pick a time and date for me to deliver her mattress in the next 30 days, stating that if I didn’t get a time to return her property, I’d get her a donation receipt from a charity.

She hung up on me. Two hours later, she appeared at my door to take her mattress back, didn’t say a word, wouldn’t allow me to help her with carrying it, and hasn’t spoken to me since. While I am still grateful that she came through with the help I needed, was it wrong for me demand the use of my living room?

GENTLE READER: We are all aware that one good deed deserves another and that two wrongs do not make a right. But nowhere, in the algebra of cliches, does one good deed cancel out a bad one.

If your friend needed a temporary home for her mattress, she need only have asked -- and it might have been difficult for you to refuse. But she did not, leaving you little choice but to do what you did. Miss Manners awards you extra credit for being polite throughout, and for remaining grateful for the original favor in spite of the subsequent behavior.

DEAR MISS MANNERS: I enjoy cooking and have a reputation for being a good cook. Often guests ask for the recipe of a dish they just had.

I have no interest in keeping my recipes secret, but the truth is, I rarely follow recipes, so I have nothing to give them. I can try to re-create a dish and write down the ingredients and techniques, but this is very time-consuming. I’m happy to do that, but only if the person is sincere in wanting to prepare the dish.

How can I tell? To say, “It’s going to take me a long time to write down a recipe, so are you really sure you plan on making this?” seems rude.

GENTLE READER: It does. Miss Manners prefers a friendly demonstration of the difficulty delivered in a slightly ditzy way: “You know, I improvise my recipes. I couldn’t for the life of me tell you how much oregano is in there.”

Those who persist can be presumed to be serious -- assuming your attempt to parry the request has not planted doubts about what they just consumed.

(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’m married, with two young children. When our kids ask my wife a question and she is doing something else (watching TV, looking at her cellphone), she does not respond or acknowledge them.

Is this proper etiquette, or is it just being rude? Is the proper thing to acknowledge the child, and tell them you will speak with them in a moment, as you’re busy?

GENTLE READER: No one enjoys being interrupted. Etiquette recognizes this, and balances the potential damage to the activity against the importance of the interjection.

Disrupting laundry-folding is different than interrupting someone blowing glass. Doing so to find out what’s on the calendar for next week is different than reporting that the house is on fire.

Debating where on the spectrum “Have you seen the car keys?” falls is one of the major activities of married life.

But context is also a factor. The breakfast table is a familial, social setting. In that case, Miss Manners disallows pleas of an important work email taking priority. All this aside, is this really the example your wife wants to set for children who will someday be teenagers?

DEAR MISS MANNERS: My cousin started dating again after many years of being divorced. It’s the first time since then that he feels comfortable being with someone. We like his new girlfriend; she is very pleasant and sweet. She moved in with him a couple of months ago.

Our family is very close. We’ll visit him about twice a month, and vice versa. During their last visit to my house, she took off her shoes and put her feet on my couch. She positioned herself where she sits on her feet, so that they are tucked in the cushions.

I was taken aback, and my first reaction was to look at my mother, who was also visiting; we just exchanged looks. I am usually a direct person, and normally I would’ve said something, but I didn’t want to just blurt out what I really wanted to say: “Get your feet off my couch!”

I’ve been told that I can come across as insensitive, but I honestly don’t mean to be. I noticed she sits like that in their house, so I am afraid that she’ll feel comfortable to do it again at mine. What should I say the next time it happens?

GENTLE READER: Life was simpler when everyone understood that undressing in front of acquaintances -- even partially, and with ones you hope might someday be something more -- was impolite. But hosts who insist that guests leave their shoes at the door have muddied the waters, if not the floor.

Your cousin’s girlfriend no doubt thinks she is both “making herself at home” and respecting your couch (by taking her shoes off). The way to get her off the couch is to offer an alternative -- ”Would you be more comfortable in this chair?” -- one without sufficient room for drawing up one’s feet. But depending on how serious you consider her infraction, Miss Manners recommends you wait and see how permanent her company is likely to be.

(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.)