Final answer:
The phrase "what makes you look so?" indicates Files' observation of something distinct or concerning in the Sergeant's appearance or demeanor, which may hint at deeper emotions or upcoming events in the story.
Step-by-step explanation:
When Files asks Sergeant, "what makes you look so?", it suggests that Files has noticed something unusual or noteworthy in the Sergeant's appearance or expression. This type of question in English literature is often used to draw attention to a character's inner state of mind or feelings, possibly foreshadowing events or revealing traits that are not immediately apparent through actions alone.
The question might be part of a dialogue in a play, book, or another piece of literature, and understanding the context is crucial for interpreting the meaning. The question reveals that Files is perceptive and attentive to the Sergeant's mood or condition, which could be important for the development of their relationship or the plot of the story.