*When there is a person who is frowning. You can say the person has a bad look on his/her face. 'The person's look is bad' doesn't really make sense, as a native speaker would be confused about 'look' in this sentence. It seems to imply that they are looking at someone in a bad way, so would need someone/thing to be looking at. Alternatively a 'look' could mean their fashion style, for example: 'he is wearing a look from the Fall/ Winter 2025 collection'.

Neither sentence sounds natural in English. If you want to describe someone's facial expression, here’s a better way to say it: ✔ "The person looks upset/angry/unhappy." ✔ "They have an unhappy/angry expression." ✔ "They have a frown on their face." Tip: - "Look" as a noun usually refers to style or appearance (e.g., "I like your new look."). - To describe facial expressions, use "looks" + adjective ("He looks sad.") or "expression" ("His expression is serious.").