This happened to me when i first got to my job and last year around this time. You have to relax your throat. Practice prolonging the first word of your sentences, making an h sound before you say words that have a hard g or k sound (i.e. gorilla or coffee), and try to anticipate when you are going to stutter in your conversations and slow down your speaking until you know that you're not going to stutter. If you are feeling really anxious just remove yourself from the situation and try to relax. You can massage your throat, take some deep breaths, and practice what you are gonna say. On your off time practice using speech techniques with tongue twisters so that you can use them easier during normal conversation