—used to say that something is required or necessary —also have got to Note: There is a difference in meaning between not have to, "it is not necessary to," and must not, "is not allowed to."
—used to say that something is required by a rule or law
—used to say that something is desired or should be done
—used to say that something is very likely
—used in various spoken phrases to emphasize a statement
—used in questions or statements that express annoyance or anger