(REAL SIMPLE) -- Some things should never be said. Here are some tips on how to avoid putting your foot in your mouth -- and what to use instead.

Don't say: "You look tired."

Why: It implies she doesn't look good.

Instead say: "Is everything OK?" We often blurt the "tired" comment when we get the sense that the other person feels out of sorts. So just ask.

Don't say: "Wow, you've lost a ton of weight!"

Why: To a newly trim person, it might give the impression that she used to look unattractive.

Instead say: "You look fantastic." And leave it at that. If you're curious about how she got so svelte, add, "What's your secret?"

Don't say:: "You look so good for your age."

Why: Anything with a caveat like this is rude. It's saying, "You look great -- compared with other old people. It's amazing you have all your own teeth."

Instead say:"You look great." Real Simple: Easy ways to exit awkward situations

Don't say: "I could never wear that."

Why: It can be misunderstood as a criticism. ("I could never wear that because it's so ugly.")

Instead say: "You look so good in skinny jeans." If you slip, say something like "I could never wear that...because I wasn't blessed with your long legs."

Expert: Clinton Kelly, cohost of the TLC show, "What Not to Wear."

What not to say in the workplace

Don't say:"That's not my job."

Why: If your superior asks you to do something, it is your job.

Instead say: "I'm not sure that should be my priority right now." Then have a conversation with your boss about your responsibilities. Real Simple: How to be nice

Don't say: "This might sound stupid, but..."

Why: Never undermine your ideas by prefacing your remarks with wishy-washy language.

Instead say: What's on your mind. It reinforces your credibility to present your ideas with confidence.

Don't say: "I don't have time to talk to you."

Why: It's plain rude, in person or on the phone.

Instead say: "I'm just finishing something up right now. Can I come by when I've completed this?" Graciously explain why you can't talk now, and suggest catching up at an appointed time later. Let phone calls go to voice mail until you can give callers your undivided attention.

Expert: Suzanne Bates, president and chief executive officer of Bates Communications, an executive-training firm in Wellesley, Massachusetts, and author of "Speak Like a CEO."

What not to say during a job interview

Don't say: "My current boss is horrendous."

Why: It's unprofessional. Your interviewer might wonder when you'd start bad-mouthing her. For all you know, she and your current boss are old pals.

Instead say: "I'm ready for a new challenge" or a similarly positive remark.

Don't say:"Do you think I'd fit in here?"

Why: You're the interviewee, not the interviewer.

Instead say: "What do you enjoy about working here?" By all means ask questions, but prepare ones that demonstrate your genuine interest in the company.

Don't say: "What are the hours like?" or "What's the vacation policy?"

Why: You want to be seen as someone who focuses on getting the job done.

Instead say: "What's the day-to-day like here?" Then, if you've really jumped through every hoop and time off still hasn't been mentioned, say, "Can you tell me about the compensation and benefits package?"

Expert: Mary Mitchell, president of the Mitchell Organization, a corporate-etiquette training firm in Seattle, and author of "The Complete Idiot's Guide to Etiquette."

What not to say about pregnancy and babies

Don't say: "Are you pregnant?"

Why: You ask, she's not, and you feel totally embarrassed for essentially pointing out that she's overweight.

Instead say: "Hello" or "Great to see you" or "You look great." Anything besides "Are you pregnant?" or "What's the due date?" will do. Save yourself the humiliation and never ask.

Don't say: "Do you plan on breast-feeding?"

Why: The issue can be controversial, and she may not want to discuss her decision publicly.

Instead say: Nothing. Unless you're very close, don't ask. If you slip, make up for the blunder by adding, "And do you feel comfortable telling me?"

Don't say: "Were your twins natural?" or "It must have been hard for your child's birth parent to give him up."

Why: You're suggesting that natural conception is better than in vitro fertilization (IVF) or adoption.

Instead say: To a parent of multiples, try a light "Wow, you have your hands full!" To an adoptive parent, say the same stuff you would to any other parent: "She's adorable!" or "How old is he?"

Expert: Kim Hahn, founder and chief executive officer of "Conceive" magazine.

What not to say to a single (or newly single) person

Don't say: "You were too good for him."

Why: You are basically saying she has bad taste. And you'll be embarrassed if they ever patch it up.

Instead say: "His loss!" It gets the same point across without disparaging her judgment. Real Simple: How to express sympathy

Don't say: "I'm glad you got rid of him. I never liked him anyway."

Why: She'll wonder about your fake adoration for him while they were together.

Instead say: "I'm confident you'll find someone who will give you exactly what you want." It focuses on what's to come, not on the dud you're glad she's done with.

Don't say: "How could someone as perfect as you still be single?"

Why: A statement like this comes off as a backhanded compliment. What she hears is "What's wrong with you?"

Instead say: "Seeing anyone?" If she's tight-lipped about her love life, move on to other topics.

Expert: Bethany Marshall, Ph.D., a psychotherapist in Beverly Hills and the author of "Deal Breakers: When to Work On a Relationship and When to Walk Away."

What not to say during a fight with your beloved

Don't say: "You always" or "You never" or "You're a [slob, jerk]" or "You're wrong."

Why: Speaking in absolutes like "you always" and "you're wrong" is playing the blame game, and resorting to name calling makes your partner feel helpless, which puts him on the defensive and makes a bad fight worse.

Instead say: "I'm upset that you left the dishes in the sink again. What can we do so that this stops happening?" Starting with the pronoun I puts the focus on how you feel, not why he's in the doghouse, and it will make him more receptive to fixing the problem.

Don't say: "If you really loved me, you would..."

Why: The more you treat your partner as if he'll never satisfy you, the less satisfied you'll be. Controlling your partner by imploring him to do something isn't a good way to build intimacy.

Instead say: "I feel taken for granted when you don't help around the house. I would feel better if we could..." The best way to keep a productive fight from becoming a dirty one is to be clear about why you're upset and then offer a solution.

Expert: Terrence Real, a family therapist in Newton, Massachusetts.

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