Have a long face is an expression used to describe someone who looks sad or depressed. It can be caused by a variety of things, such as disappointment, grief, or even boredom. Two words that are commonly used to describe this expression are 'MOPE' and 'SULK'. MOPE is defined as to be listless or dejected, while SULK is defined as to be sullen or morose. Both words are four letters in length and can be used to accurately describe the expression have a long face.