DEAR ABBY: The letter from "Stephanie in Delaware," regarding the compliment she received in high school, reminded me of a compliment that changed my life.

Last September, I was flying home from Pittsburgh. I am one of those "oversized" women who take up the entire airline seat. The plane had three seats on one side of the aisle. Two seats on the other. I had the window seat on the side with two seats.

A good-looking gentleman (if you consider a Cary Grant look-alike good-looking) sat down beside me. He greeted me with a "Good morning," and a great smile. As he buckled his seat belt, he said, "I always feel cramped in these seats. Would you mind if I raised the armrest between us?" I know he didn't feel cramped. He wanted to make sure I was more comfortable.

During our flight, he complimented me on my hairstyle and the "lovely dress" I was wearing. His remarks had a lasting effect on me, Abby. Since that flight, I have lost 23 pounds, thanks to a gentleman who didn't scowl at an overweight woman, but instead, made her feel attractive. -- SLIMMING FAST IN FLORIDA

DEAR SLIMMING FAST: It's not the first time an attractive man has provided the incentive for a woman to do the right thing. Or the wrong thing, for that matter.

DEAR ABBY: Should I tell my ex-husband that our sons (8 and 11) told me they hate his new wife and "can't wait for them to get divorced"?

Although the boys didn't tell me NOT to say anything, I don't want to break a confidence, or worse yet -- make things more awkward than they already are at their dad's house. The boys are with them every other weekend.

Their stepmother is very moody and seems to enjoy belittling children -- including her own teen-agers, who are now exhibiting behavior problems.

Abby, I love my sons and feel it would be in their best interest if their dad knew how they felt about their stepmom. Your advice would be appreciated. -- CONCERNED MOM IN CENTRAL CALIFORNIA

DEAR MOM: Instead of being the town crier, urge your sons to speak for themselves and tell their father why they feel as they do. If it's possible for your ex-husband to encourage his wife to build a better relationship with the boys, it would be a far more effective motivator than anything you could say.

DEAR ABBY: My buddy and I have an ongoing debate about whether it's necessary to tip a person who delivers furniture. Everybody knows that pizza delivery people get tips, but shouldn't other kinds of delivery people as well?

Furniture deliverers move heavy objects like couches, armoires and beds -- and they often assemble the items they deliver. Sometimes they're also willing to haul unwanted furniture and appliances off the premises.

What's your opinion, Abby? Is tipping necessary? -- TWO GUYS IN MINNESOTA

DEAR GUYS: Tipping isn't mandatory. However, if the delivery person has done a good job and nothing is damaged, and some items required assembly, I see no reason why a gratuity should not be offered.

For everything you need to know about wedding planning, order "How to Have a Lovely Wedding." Send a business-size, self-addressed envelope, plus check or money order for $5 (U.S. funds only) to: Dear Abby, Wedding Booklet, P.O. Box 447, Mount Morris, IL 61054-0447. (Postage is included.)

DEAR ABBY: I am a lifeguard at a public swimming pool. Please inform parents that the presence of a lifeguard does not guarantee the safety of their children.

Young children don't have the maturity to understand the risks posed by water and often will not stay in the depth that is safe for them. Besides giving verbal warnings that can go unheeded, there is little a lifeguard in a tower 30 feet away can do to keep a child out of deep water. Also, drowning is silent. Victims can hardly breathe and therefore cannot scream for help.

One day last summer, my co-workers and I rescued five children. They were all under the age of 6, all unattended, and all were drowning within a few feet of other swimmers. No one but us realized anything was wrong. One of those kids was a 5-year-old girl whom I had repeatedly told to stay in the shallow pool.

Parents, PLEASE don't let the eyes of a lifeguard be all that stands between your child and death. We do our job well, but we're only human. Swim with your inexperienced younger kids, and stay within arm's reach at all times. -- CONCERNED LIFEGUARD IN THE ROCKIES

DEAR CONCERNED: Children should be taught to swim as early as possible. And they need to be taught the rules of water safety. Even then they should be supervised AT ALL TIMES at both public and private swimming pools. To do anything less is to invite a tragedy.

And while we're on the subject of near disasters in the water -- read on:

DEAR ABBY: While swimming at a New Jersey beach, my husband became caught in a riptide. He struggled to swim toward land, but the current pulled him farther and farther out to sea.

There were several adults nearby. He pleaded for help several times, but got no response. He was later told that they thought he was only kidding!

Luckily, a boy about 12 years old took him seriously. The boy swam toward my husband and extended a boogie board for him to grab. By then, my husband was completely exhausted and out of breath. With the boy's help, and later that of a lifeguard, my husband was brought safely back to shore.

Abby, please inform your readers that when a person pleads for help in ANY situation, the person should be taken seriously! It is far better to offer assistance or to seek additional help than to assume it's only a joke. My husband firmly believes that if that boy had not tried to help, he would not be here today. -- ELEANOR M. GLENSIDE, PA.

DEAR ELEANOR: Your husband is a lucky man. His experience proves that sometimes children are smarter than adults. The boy who came to his rescue is a true hero.

DEAR ABBY: I love my boyfriend very much and am planning to offer him a proposal of marriage. We have a child together, and I feel it's time for me to grab life by the horns and run with it.

Is there any rule of etiquette that says I have to buy him a gift -- and if so, what should it be? I'm clear on where our wedding should take place, the decorations, guest list, etc., but it's this last detail of gift-or-no-gift before I pop the question that I'm not sure about. -- HOPEFUL BRIDE-TO-BE, COLUMBIA, MO.

DEAR HOPEFUL: I think the child was gift enough. Give him nothing extra unless he says yes to your proposal.

Abby shares more than 100 of her favorite recipes in two booklets: "Abby's Favorite Recipes" and "More Favorite Recipes by Dear Abby." Send a business-size, self-addressed envelope, plus check or money order for $10 (U.S. funds)

to: Dear Abby -- Cookbooklet Set, P.O. Box 447, Mount Morris, IL 61054-0447. (Postage is included in price.)

DEAR ABBY: I am a 33-year-old HIV-positive man. Last week at my office, I was shocked when two of my co-workers declared that they could tell whether or not people are HIV-positive just by looking at them.

Abby, this is no laughing matter. Please inform your readers that someone can be HIV-positive and appear to be physically healthy. I shared my health status with my office mates, and by doing so, I hope I have changed some minds by shattering that myth. Sign me ... POSITIVE IN D.C.

DEAR POSITIVE: Not everyone would have been so generous or courageous, because there is still a lot of prejudice, ignorance and misunderstanding when it comes to HIV. There is more than one lesson to be learned from your letter.

(1) You CANNOT tell a person's HIV status by his or her appearance.

(2) It is imperative that couples not have unprotected sex unless both partners have been screened for HIV.

DEAR ABBY: I am a 12-year-old girl who is dating a senior boy in high school.

One night, we went to a party and then back to his place. His parents and sister were out of town, and he was really drunk.

As soon as we got to his house, he started drinking again. That led to a big fight. I was literally walking out the door when he grabbed me and told me if I ever leave him, he'll hunt me down and kill me!

Abby, ever since that night, I've been scared of him. Please tell me what to do. -- SCARED IN MAXTON, N.C.

DEAR SCARED: Tell your parents or guardian about the young man's threat. You are too young to deal with this yourself and to be dating a boy that much older than you.

He clearly has problems and not enough supervision -- and the same is true of you.

P.S. Under no circumstances should you be riding in a car with a driver who has been drinking. That, too, could cost you your life.

DEAR ABBY: My sister-in-law, "Barbara," and her family are avid karaoke fans. They've had a machine for 10 years, and every time we go to their home, no matter the occasion, they sing at the drop of a hat.

When relatives visit from out of town -- they sing. They sing at Christmas, birthday parties, wedding receptions -- and the volume is set so high that it's impossible to carry on a conversation. If you leave the room to talk, they'll turn on the intercom so the music is carried throughout the house. It's true they encourage others to join in -- but they never give up the microphone.

Barbara is not the kind of person who takes criticism well. Some members of the family tease her about singing so much, but she doesn't take the hint.

Please help me find a way to convince Barbara that we don't need to be "entertained" all the time. -- TONE DEAF IN INDIANA

DEAR TONE DEAF: That may be impossible. We both know you can't change them. They have show biz in their blood. Wear ear plugs if necessary and be grateful they don't have a cover charge and a two-drink minimum.

To receive a collection of Abby's most memorable -- and most frequently requested -- poems and essays, send a business-sized, self-addressed envelope, plus check or money order for $5 (U.S. funds) to: Dear Abby -- Keepers Booklet, P.O. Box 447, Mount Morris, IL 61054-0447. (Postage is included in the price.)