Pull a long face is an idiom used to describe someone who looks unhappy or sad. There are a variety of synonyms that can be used in place of this phrase, including "look glum," "wear a frown," "sport a sour expression," "have a downcast countenance," or "display a gloomy demeanor." These alternative phrases can be used to depict various levels of sadness or sorrow, ranging from a mild case of disappointment to a more serious bout of melancholy. Regardless of the specific phrase used, each conveys the sense that someone is not in a good mood or is feeling unhappy about something.