Must

"Must" is a modal verb used to express obligation, necessity, or a requirement. It indicates that something is mandatory or essential, often determined by rules, laws, or strong advice. For example, "You must wear a seatbelt" means wearing a seatbelt is required by law. It emphasizes that there are no real alternatives or exceptions in that situation. "Must" can also suggest a strong recommendation or logical conclusion, such as "If it's raining, the ground must be wet." Overall, it communicates that something is unavoidable or must be done.