You probably have no idea that it's happening.

But when you open your mouth, or let your fingers dance across the keyboard, you may be killing your own credibility in the ears and eyes of whomever you are trying to impress.

In many cases, you know exactly what you want to communicate to someone, but for whatever reason, you have an inability to communicate it properly. And that can send doubts racing through their mind.

The result may be that you'll achieve the very opposite of what you intended to do.

You won't get that contract.

You won't get that promotion.

You won't get hired.

And once you've lost the credibility you were hoping to establish, it can be extremely difficult to get it back.

Here's a list of some of the most common credibility-killing phrases we are guilty of using. Do any of them hit home for you?

1. "Like, uh, um. . ."

We all do this! It's called a disfluency, and it's a break or irregularity in our speech. Where it becomes a problem is when we pepper our patter with "uh" or "like" far more than is normal. It makes us sound nervous and not at all sure of ourselves.

2. "Hopefully. . ."

This and "kind of" and "sort of" are examples of unnecessary qualifiers. Don't hope. It marks you as unsure. Know what you want, and then make it happen. And don't say "kind of" if you can help it. Find a better way to explain what you're trying to say.

3. "I'll try."

Yoda would have a field day with this one, but he was right. You can either do something, or not do something. Don't "try." Be sure of your ability to succeed.

4. "If that makes sense."

No. Don't leave this up in the air. Your job is to ensure that something makes sense. If the words you're using aren't good enough to achieve this goal, find better words.

5. "Let me get back to you on that."

If you're talking with someone about a product or service that you want them to consider, you need to know it inside and out so you can answer any questions about it. A statement like this may seem harmless, but it could make you look like you don't know as much as you should.

6. "Honestly. . ."

This is another lazy qualifier, but it could have additional unwanted consequences. If you qualify your statement with the word "honestly," it might make someone wonder if you're not being honest at other times.

7. "We are literally going to knock your socks off."

This means I'll be in bare feet. Learn the difference between "literally" and "figuratively." And then never use "literally" in your speech unless you are actually being literal.

8. "It's not my job/fault."

Maybe it isn't, but dodging responsibility or blaming someone else doesn't make you look very professional. If there's a problem, step up and own it. Make it better. A customer or client doesn't care about all of the drama; they want to know what you're going to do about it.

9. "On the bright side. . ."

Spinning bad news seems like a natural thing to do. We want to cushion the blow whenever possible, especially if the blow might make us look bad. But people will appreciate the truth if you just leave it at that. If they think you're trying to minimize the bad news in order to save face, they'll remember it.

10. "Why should I care?"

Arrogance is similar to blaming. If you have an opportunity to take control of a situation, seize that opportunity. Someone will appreciate your initiative. Conversely, if they don't think you're capable of taking the lead, you won't be entrusted with such opportunities.

11. "That guy can't do his job."

You might think that belittling someone else is a great way to make yourself look better by comparison, but you'd be wrong. Insecure people do this, and secure people recognize it when it happens. It won't work out in your favor, so don't do it.

12. "This is the best thing ever!"

This is an example of exaggeration and hyperbole, something many of us frequently do. But if you're going to make a grandiose statement, especially when you can't prove it, don't be surprised if you get tuned out in a hurry.

13. "We maintain our product to the highest standards."

This is an unnecessarily vague statement. What standards are you talking about? And how do you measure your product to these standards? Again, you need to be able to back this up.

14. "We will actualize a plan to synergistically create. . ."

Nobody wants to hear your buzzwords. Few things will turn us off faster than this. Talk to us in plain English.

15. "The product was involuntarily incapacitated."

Not buzzwords, per se, but formal or technical jargon will make our eyes glaze over. Don't talk over someone's head. They won't understand your message, and they may devalue it as a result.

It's worth taking the time to improve your communication skills so you won't have problems caused by these or other credibility-killing phrases.

Practice your patter. Go over it as much as you need to. And improve your self-talk in general. Your confidence in yourself will show in the way you speak about your field of expertise.

Often, we ourselves are the biggest obstacles we will find on the road to success. Improve your vocabulary and get out of your own way!