FORTUNE — After fraud, theft, flood, and fire, the most dangerous word to use in the workplace today is short, sweet, and fraught with peril: try.
Whether in a job interview, on a resume, or in the office, try simply shows a lack of belief, passion, commitment, and confidence — all the qualities you need to succeed in today’s tight job market. Grammarly’s contextual thesaurus has a whopping 66 different synonyms for try, yet none of them are as convincing as words like do, believe, act, tackle, accomplish, or succeed. While try might get you 10%, or even halfway there, employers are looking for strong problem solving skills and unwavering dedication.
I cringe when I hear, “I’ll give it a try,” because the phrase suggests failure. “I’ll do it” inspires confidence every time.
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On a resume, try indicates a task or responsibility that is either incomplete or vague; it is one of the few three-letter words that can get your resume moved to the rejection pile. It may be even worse than all of those famous four-letter words. On the other hand, action verbs backed up by facts and examples can make a resume — and an individual — stand out.
Likewise, in an interview, when candidates are required to be sharp and precise, try comes across as uncertain at best. Hiring managers are looking for someone with a spark in his or her eyes and confidence in his or her voice. The words you use matter, a lot.
If you contact a company and request action on an issue, hearing “I’ll try” isn’t going to alleviate your frustration; as a matter of fact, it’s more likely to exacerbate the problem. Likewise, when I hear employees say they will “try to meet a deadline,” “try to close a deal,” or “try to handle a customer issue,” my next question is what we need to do to ensure their success. When asked to complete a task that you do not feel is realistic, it’s better to suggest a more feasible goal. Managers appreciate problem solvers and employees who come to the table with solutions rather than problems.
While try is the most dangerous word that an employee or jobseeker can use in the workplace, there are certainly other “danger words” that also indicate negativity, uncertainty, or controversy at work: someday, if, never, maybe, used to, can’t, and excessive acronyms or slang can also doom your chances of getting (or keeping) a job.
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Ultimately, words carry plenty of power in both verbal and written communication. Your cover letter and resume account for your first impression to a potential employer. Successive phone and in-person interviews can enhance or detract from that impression, and the way you carry yourself in day-to-day business interactions — from emails to meetings to reports to customer interactions — will determine your reputation in the workplace. When you use words with power and impact, and deliver on expectations, you are sharpening your image, bolstering your potential, and giving your career a chance to shine.
So don’t try, do; don’t doubt, believe; and don’t wonder, act.
Brad Hoover is CEO of Grammarly.