What you say at work can launch your career forward or hold you back.

A deliberate choice of words can boost your professional reputation and credibility, strengthen your relationships and set the pace for upward mobility at work. Poor communication and negativity can have the opposite impact, making it hard for people to connect with you and calling your reliability into question.

Highly successful people understand the importance of word choice at work, and use a few key phrases regularly to propel themselves professionally, according to leadership experts.

Here are three powerful phrases experts recommend using to appear smarter, more thoughtful and more trustworthy on the job.

'I need help'

Amy Dickinson, 64, shared life advice in her widely syndicated news column, "Ask Amy," for two decades. In her final column, she condensed her advice into a handful of key phrases. The first one? "I need help."

It's arguably the most difficult phrase for people to incorporate into their lives, experts say, because having to ask for help can make you feel vulnerable, unintelligent or like you're not in control. But doing so can boost your rapport and relationships in the workplace, according to bestselling author and leadership expert Simon Sinek.

It's "such a common misunderstanding" that asking for help makes you seem weak — people are actually more inclined to trust you when you ask them for assistance than the other way around, Sinek said during a conversation with comedian Trevor Noah at the Brilliant Minds 2024 conference.

If asking for help is difficult for you, try doing it in lower-stakes situations first, like seeking suggestions for what to make for dinner or which dog parks your friends and colleagues like the best, according to leadership coach M. Nora Bouchard. Over time, you'll grow comfortable leaning on others in tougher situations.

"Try to create this team of helpers, so that asking for help later on when you really need it isn't such a big deal," Bouchard said in 2020.

'I hear what you're saying'

A huge part of learning, building connections and growing at work is listening. If you want people to be attentive to your ideas and perspectives, you've got to do the same for others.

The next time you're in a meeting and want to interject, instead of cutting someone off or abruptly entering the conversation, listen actively and intently and wait for them to finish their thoughts, says communications expert and speaker Jessica Chen.

Before giving your own insight, start with, "I hear what you're saying."

"These words will show the person that you're acknowledging them and their thoughts, even if you have an opposing point of view," Chen wrote in August. "You don't want the other person getting defensive, which can prevent them from considering what you have to say."

'I don't know, but I will find out and come back to you'

Sometimes, even giving a wrong answer can seem better than saying "I don't know" at work. The thought of appearing unprepared or unknowledgeable can be stressful, especially in a big team meeting or in conversation with more senior colleagues.

But admitting you don't have the answer shows vulnerability and emotional intelligence, along with a willingness to be transparent. At the same time, show that you're willing to find a solution, according to Rupal Patel, an executive advisor and former CIA agent.

"Too many people feel pressured to fill silence with made-up, ad-hoc responses. Doing this can break trust, rupture relationships and harm organizations," she said in June. "It's the ultimate sign of humility and thoughtfulness when you can confidently say what you don't know."

Patel admitted "I don't know" is a phrase she used often while working at the government agency — and one she still uses today.

"Using this phrase in my career has earned me the trust of four-star generals, ambassadors, investors, board members and many other important stakeholders," she added. "They may not have been on my side when we started the conversation — but they were at the end of it, because they knew that they could rely on me to be thorough and have conviction in what I brought back to the table."

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