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must v. v.aux.
1.To be obliged or required by morality, law, or custom.
2.To be compelled, as by a physical necessity or requirement.
3.Used to express a command or admonition.
4.To be determined to; have as a fixed resolve.
5.Used to indicate inevitability or certainty ex. We all must die.
6.Used to indicate logical probability or presumptive certainty.