The phrase "have butterflies" is a common expression used to describe that feeling of nervousness or excitement in one's stomach. There are several synonyms that can be used to replace this phrase, including "feeling jittery," "having a fluttery tummy," "having a case of nerves," "being in knots," "feeling anxious," "being apprehensive," or "having a queasy stomach." These phrases can be used in a variety of situations, such as before a presentation, a job interview, a first date, or any event that might cause a mix of emotions. While having butterflies is a natural response to certain situations, it's important to take deep breaths and remain calm to avoid being overwhelmed by nervousness.