DEAR ABBY: Recently my husband and I invited his son and daughter-in-law for dinner. We also invited two other couples. They know each other, so we felt confident everyone would be comfortable. Our guests seemed to have a great time.

A few days later, I received a note from the wife of my husband's son. It read: "Thank you for having us for dinner last Thursday. Everything was lovely! However, we would have dressed more appropriately had we known it was going to be a 'dinner party.'"

They both had worn jeans. The husband of the second couple came dressed in a coat and tie, and the third couple called beforehand to ask if the men should wear a tie. I said no.

How should I respond to this note? -- PERPLEXED IN TEXAS

DEAR PERPLEXED: Tell the young woman how pleased you were that they could attend and how much their presence added to your dinner party.

Suggest to her that in the future she might do as you do when you're not sure of the "dress code": Call ahead and ask what others will be wearing so that embarrassment can be avoided.

DEAR ABBY: My youngest son, "Jason," is a senior in high school and an all-around good kid. All of a sudden he's decided to let his hair grow. Although it's really not that long, my husband is very critical of it and threatens to cut it almost every day.

I feel it's time for Jason's dad and me to let him make some decisions on his own. His hair doesn't bother me as long as he maintains his grades, behaves himself and keeps it clean. (I don't think it's any longer than the Beatles when they first came on the scene.) I look at other boys our son goes to school with, and some of them have short hair, while others wear theirs Jason's length or longer.

What do you think about this? How can I convince my husband to back off? (He let his hair and sideburns grow when he got out of the service.) -- PEACEMAKING MOM IN ARIZONA

DEAR PEACEMAKING MOM: If your son is doing well socially and academically and keeps his hair clean, your husband should not turn its length into a control issue. Learning to make decisions is an important part of a teen's development. It's also important for parents to pick their battles carefully.

P.S. Dig out some photos of your husband with longish hair and sideburns and tell him it's time to get back in touch with his sense of humor and stop obsessing about things that are not important.

DEAR ABBY: My cousin's daughter, "Lisa," plans to be married in May. She is a 34-year-old schoolteacher and her fiance is a successful 39-year-old radiologist. He has just informed her that she must sign a pre-nup or there will be no wedding.

Abby, Lisa has asked me for advice about this, and I'm not sure what to tell her. When I heard about the pre-nup, my first reaction was she should walk -- but now I'm not so sure. Could you share your thoughts on this? -- AWAITING A REPLY IN NEBRASKA

DEAR AWAITING: A prenuptial agreement is for the protection of both parties. Rather than advising the young woman to "walk," tell her to get a lawyer of her own to review and explain the document before she signs anything.

For everything you need to know about wedding planning, order "How to Have a Lovely Wedding." Send a business-sized, 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 in the price.)

DEAR ABBY: My husband, "Max," and I have been married for 12 years and have two precious children. We trust each other 100 percent. Our problem is we're friendly with a couple who have a 15-year-old girl, "Tina." Every time we go there, Tina throws herself at my husband.

The girl wears skimpy clothes, touches Max, makes suggestive remarks, and appears to really have "a thing" for him. He has told her repeatedly that he's not interested and that she's "just a kid," but she hasn't taken the hint to back off.

We've talked to her parents. They say we're reading too much into their daughter's behavior. My husband and I have argued over this, and it's putting pressure on our marriage. I don't want to give up our friends, but I also don't want my marriage to be wrecked by that little slut.

I know Max would never try anything with Tina, but she's the kind who might blame a man if she doesn't get what she wants. How can we get her to cool off? -- MARRIAGE ON THE ROCKS IN BRITISH COLUMBIA

DEAR MARRIAGE ON THE ROCKS: Put as much distance as you can between yourselves and this couple -- or see them only away from their home. If Tina is capable of lying if she doesn't get her way, she's trouble. The smartest thing your husband could do is avoid her.

DEAR ABBY: I am unemployed and looking for work. Unfortunately, my field is shrinking. There is little opportunity for jobs in the future. I am considering returning to school and majoring in health care. It's something that has always interested me -- and it's a growing field.

My problem? My fiancee, "Phoebe," is dead set against me changing careers. She says it's not possible to go to graduate school and maintain a relationship. I find her attitude to be hypocritical since she has an advanced degree and a lucrative income.

I love Phoebe, but I'm tired of being poor and having no job prospects. I don't want to lose her; however, I am frustrated. I've tried talking to her. She won't discuss it and has given me an ultimatum: school or her. What do you think? -- JOB CHANGE IN VERMONT

DEAR JOB CHANGE: A woman who loves you should want what is best for you. Remaining in a field that is being phased out would leave you financially vulnerable. I urge you to return to school and safeguard your future. It appears Phoebe does not value your happiness, or she would have your best interests at heart.

DEAR ABBY: Our 15-year-old son, "Brian," just started dating a 14-year-old girl I'll call Jenny. They are both good kids. The problem is they have no hesitation about kissing in front of us or anyone else. They also snuggle on our couch whenever they can. Last night, they began kissing in the back seat of our car while my husband and I sat in the front. It was as though we weren't even there.

We feel Brian and Jenny are becoming too intimate too fast, and we're worried their hormones will supersede their better judgment. Fortunately, we have a very open relationship with Brian, but we don't know what to say to him about this. Any suggestions? -- TOO YOUNG TO BE GRANDPARENTS

DEAR TOO YOUNG: You bet. Get to know Jenny's parents and express your concerns to them. Both teens need to be involved in activities other than each other. Your son -- and Jenny -- also need to know everything there is to know about human reproduction and its prevention. (There are many books on the subject.) Do not depend on schools to perform this parental responsibility for you. Many schools now teach the students nothing beyond abstinence.

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: My fiance, "Doug," just revealed to me that for the past six months he's been using drugs. We've been together almost four years and our wedding is scheduled for next month. We are both in our early 20s.

Doug confessed that he has been using money we set aside for bills to buy drugs. He said he has also stolen money from our best friend for the same purpose.

He came to me on his own to tell me all this. Doug has always been a sweet, caring guy. I love him with all my heart, but I've lost my trust in him. Now I don't know what to do. I can hardly believe this is happening. I still want to marry him, but don't want to marry someone I don't trust. What should I do? I need an answer in a hurry. -- HURT AND CONFUSED IN FLORIDA

DEAR HURT AND CONFUSED: You have just had a peek at what life is like with an addict. Postpone the wedding indefinitely until your fiance has been through rehabilitation and is established in a 12-step program. You may love him -- and vice versa -- but there is a side to your fiance that you're just getting to know. I urge you to be sure he's clean before you make a lifetime commitment.

DEAR ABBY: Friends of ours, "Cindy and Josh," are moving a few states away and throwing a goodbye party for themselves. Are my husband and I required to take a gift to the party? They were married a few months ago, and we were very generous with their shower and wedding gifts.

Josh has been unemployed for more than a year. According to Cindy, he doesn't like to job-hunt, so he's waiting for something to "fall in his lap." On the other hand, Cindy has a well-paying, full-time job. They live rent-free in a house his parents own, and spend their money on sports memorabilia, stereo equipment, electronic gadgets, etc.

Neither one has a job waiting in the city where they're relocating, but they were given money by Cindy's parents to cover moving expenses and rent for the first few months. Cindy is hinting broadly that she expects cash as gifts.

I thought gifts were required only at housewarmings -- not farewell parties. However, my husband doesn't want us to appear cheap. Your thoughts, Abby? -- QUESTIONING COUPLE IN MISSOURI

DEAR QUESTIONING COUPLE: Although you are not required to take a farewell gift to the party, a token gift would be thoughtful. A small "jam jar" might be appropriate, because I predict they'll encounter more than one along the way. (A book on money management would also be appropriate -- and helpful.)

DEAR ABBY: I am a 15-year-old freshman in high school. My problem is that my math grades stink. Each night I try hard to double-check my math homework, but when it gets graded the next day, I always end up missing six or seven out of 10 questions.

I've asked my parents for help. They say it's been too long since they tackled math, and it's beyond them. Help! -- GOTTA GET GOOD GRADES IN WYOMING

DEAR GOTTA GET GOOD GRADES: You need a tutor. A junior or senior math-whiz who's patient could help you turn things around. Talk to your math teacher or school counselor before you fall further behind. They're there to help. Good luck.

For an excellent guide to becoming a better conversationalist and a more sociable person, order "How to Be Popular." Send a business-sized, self-addressed envelope, plus check or money order for $5 (U.S. funds) to: Dear Abby -- Popularity Booklet, P.O. Box 447, Mount Morris, IL 61054-0447. (Postage is included in the price.)