In such a competitive world, the last thing you need to do is undercut yourself. But that's what a lot of us are doing when we communicate in ways that make us sound less confident, less determined, and less sure of ourselves.

But there's an effective solution: Swap out weak words and phrases for ones that will make you come across as more professional and capable.

Here's what psychologists, linguists, recruiters and CEOs say you should avoid using if you want to get ahead, along with simple replacements that will make a big difference in how you are perceived:

1. "Does that make sense?"

What to say instead: "What are your thoughts?" or "I'd like your input on this."

If you ask "Does that make any sense?" after you've finished sharing a thought, you're immediately giving the impression that you're not convinced yourself, that your idea might be incomplete.

Rather than seeking validation or approval, you should be asking the listener or reader for their opinions on your idea.

2. "Maybe we should try ..."

What to say instead: "Let's try…" or "It's a good idea to try…"

Up until the mid-19th century, "maybe" was written as two words — "may" and "be" — which makes it clear that it literally refers to something that might happen, but might not.

That's pretty wishy-washy when you apply it to your own ideas or suggestions. Either you believe in what you're talking about, or you don't. 

3. "I think this would ..."

What to say instead: "I believe this would …"

This is a minor distinction, but a valid one: "I think" sounds weaker than "I believe," and is a little more doubtful, as if you're saying something might work, but you're not sure.

"I believe" puts you in charge of the thought and conveys a calm surety. And even if you're not so sure at all, no one needs to know that!

4. "I'm not positive, but …" or "I'm not sure, but …"

What to say instead: Whatever you were going to say after the "but"

You don't need to add disclaimers. Similarly, if you start your sentence with "I know this might be a stupid question, but …" or "I don't want to sound pushy, but …," you're undermining yourself.

It's an easy rule that bears repeating: Don't put yourself down. Ever.

5. "I just wanted to touch base ..."

What to say instead: "I wanted to touch base ..."

How many times have you started an email with "Just wanted to ask you if …"? The problem in this case is that the "just" is a softener — almost an apology, as if you're saying, "I hate to bother you, but …"

There's a time and a place for that, but business communication generally isn't.

6. "Needless to say ..."

What to say instead: Nothing

"Needless to say" comes from a long line of ironic phrases where you open a topic by saying you're not going to say something, but then say it anyway. So why do it?

7. "In my opinion ..."

What to say instead: Nothing

Cut to the chase and remove the unnecessary, weak intros. Whoever is listening to you or reading what you've written knows that it's your opinion or your belief. That's why you're telling them whatever you're telling them!

8. "For what it's worth …"

What to say instead: Nothing

This is another intro that makes it sound as if you're not convinced yourself about what you're saying. And if you're not convinced about your point, why should anyone else be?

9. "Sorry"

What to say instead: "Excuse me"

It's fine to apologize if you've done something wrong and need to own up to it, but too many people toss in a "sorry" and wind up weakening their image. Why say "Sorry to bother you," when a simple "Excuse me" is shorter, snappier and less self-deprecating?

Psychologists suggest that people tend to think those who overuse "I'm sorry" are ineffectual and lack confidence. If you need more convincing, keep in mind that from the 13th century on, the word "sorry" was used to mean "wretched" or "worthless."

Another similar one to avoid: "I hate to ask, but …" Just ask!

10. "[X] was developed to increase [X]."

What to say instead: "I developed [X] to increase [X]."

"I developed [X] to increase [X]" sounds more confident because it uses the active voice instead of passive voice.

With the passive voice, the subject has something done to it; with the active, the subject is doing the action. So if you created a new marketing campaign to increase brand awareness, why not use the active voice and take credit for it up front?

11. "... if you know what I mean"

What to say instead: Nothing

We've seen so many people end sentences with "if you know what I mean," or its truncated near-twin "know what I mean?" If you're one of them, stop now. It's a filler phrase that means nothing — and actually irritates a lot of people.

Along the same lines, avoid starting sentences with puffy phrases like "It's important to note that …" All you're doing is adding useless words. Know what we mean?

Kathy and Ross Petras are the brother-and-sister co-authors of "Awkword Moments," "You're Saying It Wrong" and "That Doesn't Mean What You Think It Means." Their work has been featured in The New York Times, The Washington Post and Harvard Business Review. Follow them on Twitter @kandrpetras.

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