Along with the way you dress, gesture, and carry yourself, your style of speaking plays a big part in how your colleagues and friends perceive you. “You need to be aware that you’re being judged by the way you talk,” says Deborah Tannen, PhD, a professor of linguistics at Georgetown University and author of You Just Don’t Understand.

From your tone and pitch to the specific words that litter your conversations (and emails), what you say can either boost or undercut your authority. Here, according to Tannen, are some common words, phrases, and linguistic tics to watch out for.

Examples: “I’m just emailing you to ask …” or “I’m just trying to figure out …”
Why it’s a problem: Ask yourself what that “just” is doing in your sentence. When you think about it, it’s there to weaken your statement or question, or otherwise soften your tone. Tannen refers to this as “hedging,” and says it often signals wishy-washiness, a lack of confidence, or even subservience.

Example: “This is the wrong course of action, in my opinion.”
Why it’s a problem: When you pack your statements with these kinds of qualifiers, you’re implying that other people could reasonably think or opine in ways that contradict what you’re saying. That kneecaps the weight of your words. These phrases are also redundant; you’re the one speaking or writing, so it’s already clear you’re stating your thoughts or opinions.

Examples: “Would you do me a favor …?” or “Can I ask you a question …?”
Why it’s a problem: While there are exceptions, you probably break these out when it’s a given the other person is going to say yes, Tannen says. Used this way, you’re telling the other person that the conversation you’re about to have is at his (or her) discretion—making him the lead in your linguistic dance. Beginning with “Do me a favor …” or “A question for you …” is a more authoritative way to begin a conversation, Tannen says.

Why it’s a problem: Some people are taught never to apologize. Tannen doesn’t agree, and says an unwillingness to apologize when you’re clearly in the wrong is, if anything, a sign of insecurity. At the same time, you don’t want to apologize incessantly. If you pack your conversations and emails with “sorry,” you’ll seem off balance and unsure of yourself.

Examples: “This is probably obvious …” or “Someone may have already thought of this …”
Why it’s a problem: Tannen refers to these as “disclaimers” and says they undercut whatever the speaker is about to say. If you really believe what you’re going to say is obvious or has already been considered, don’t say it. If not, ditch the disclaimer.

Examples: Raising the pitch of your voice at the end of a statement as though you’re asking a question, even when you’re not.
Why it’s a problem: This little quirk was once associated with “valley girl” ditses, but it has lately spread like wildfire—especially among millennials. Like other items on this list, it conveys a lack of confidence and authority, Tannen says. It also makes you sound like a bubblegum-chewing child.

The speed and tone of your voice also matter when trying to communicate power and authority. Research from Michigan State University shows subservient men tend to raise the pitch of their voices around more-dominant dudes, while alpha males lower their voices an octave. More research from San Diego State University backs up the MSU study, and also suggests speaking in a slow, deliberate way conveys authority. Take your time and speak on the low end of your natural register, and you’ll seem in-control and authoritative, these studies suggest.