When you’re the boss, people look to you for to set the standard. Subconsciously, your staff wants to be proud of you. Something that undermines this is poor grammar, either spoken or written. If you make yourself appear unintelligent via bad grammar, you aren’t living up to people’s expectations and you are sabotaging your potential for future advancement. Poor grammar can also leave a bad impression during business interactions, and affect the perception of your potential partners and prospects. Here are five of the top grammar mistakes managers make and how you can avoid them.

Their, There and They’re

These words are homophones, meaning they sound they same, but they have entirely different meanings. Spoken, their differences are understood, but mixing them up is the most common written mistake managers make. It is also the one that people spot the easiest. You can avoid making the mistake by remembering that “their” is in the possessive case, “there” is an adverb and usually refers to a place and “they’re” is a contraction of “they are.” Used correctly when writing about your competitor, it is “their business,” “a strategy to sell against them is right there in front of you” and “they’re not as good as we are.”

Your vs. You’re

These are the cousins of the “their, there and they’re” grammatical mistake and they appear about as often. “Your” is possessive, “is that your coat?” “You’re” is a contraction of “you” and “are.” “Did I hear you’re going on vacation?” is the grammatically correct sentence.

Me, Myself and I

These three words are misused in many ways. People put “me” in the wrong place. It is not grammatically correct to say “me and Steve went on a sales call.” It is “Steve and I.” When talking or writing about yourself with another person or people, put yourself last in that sentence. When trying to decide whether it is “me” or “I” in the sentence, take out the other person and speak the words out loud. You would say “give those to me,” so it is correct to say or write “give those to Gloria and me.” “I went to see Client X” becomes “Bob and I went to see Client X.” “Myself” has become one of the most misused words in business. This word should only be used when you are the direct object of your own action. “I did it myself” is grammatically correct. “The person you should call with any questions is myself” is grammatically incorrect. The proper sentence is “If you have any questions, please call me.”

Lack of Synonyms

A good vocabulary makes a good professional impression and you don’t need to use words nobody has ever heard of to make that impression. Instead, when speaking or writing an email, use synonyms to add better description. For example, “We lost three people in my department and we’re looking for qualified people to fill these openings. If you know people you want us to interview for these openings, please forward their resumes to me” could be re-worked as “We have three open positions in my department and we’re looking for qualified candidates to fill these vacancies. If you have people you can recommend for these jobs, please forward their resumes to me.”

Text Message English

As younger employees get promoted into managerial positions, the chances of them using text message English in their correspondence increases. Texting is a second nature to the millennial generation, but the language of texting is not a part of the accepted business lexicon. Until it is, avoid using terms like “u r” and “gr8” to replace the proper English words of “you are” and “great.”

What you do as a manager is more important that what you say. But if what you do is stellar, why undermine your excellence by committing grammatical mistakes that are easily rectified? Avoid these five common grammatical mistakes and you will support your actions instead of marginalizing them.