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must(4) (iou)



must aux. verb1. . No other parts used.
[Old English moste pa. t. of mot MOTE verb1 = Old Frisian mot, Old Saxon mot, muot (Dutch moet), Old High German muo find room or opportunity, may, must (German muss), Gothic gamotan find room, rel. to Middle Low German mote, Old High German muoa (German Musse) leisure, from Germanic.]
I. As pa. t. of MOTE verb1.
Expr. permission or possibility, or a wish: might, could. OE-LME.
Expr. necessity or obligation: had to, was (were) obliged to, it was necessary that (I, you, he, it, etc.) should. OE-L15.
II. As pres. t. (indic. & subjunct.), often ellipt. with verb understood or supplied from the context.
Expr. necessity: am (is, are) obliged or required to; have (has) to; it is necessary that (I, you, he, it, etc.) should; am (is, are) commanded, requested insistently, or recommended to. Also ellipt. (arch.), must go. ME.
Tennyson Seeing he must to Westminster and crown Young Henry there. A. S. Neill I must get estimates from the printers. J. Buchan Haraldsen is an invalid,..and must keep quiet. P. Roth Doing as I wished, not as I must. I. Murdoch You must both have a sip of sherry. J. Trollope Must you look so utterly suburban?
b. Expr. a fixed or certain futurity: am (is, are) fated or certain to (be or do), shall certainly or inevitably (be or do). LME.
Dryden Crowds of dead, that never must return. A. Lurie What must it be like in the winter!
c. Say (says) or feel (feels) that one has to. LME.
Wordsworth He is not content with a ring.., but he must have rings in the ears, rings on the noserings everywhere.
Expr. the inferred or presumed certainty of a fact: certainly am (is, are) or do (does); it cannot be otherwise than that (I, you, he, it, etc.) am (are, is) or do (does). M17.
Poetry Nation Review What he is thinking, because he must be thinking, / I cannot tell. Anthony Smith There must be few who have not been depressed.
III.
must have done, (a) should necessarily have done; (b) should have had to do, should have been obliged to do; (c) certainly did, it is to be concluded that I (you, he, it, etc.) did. LME.
Swift Had this point been steadily pursued..there must probably have been an end of faction. E. Bowen In the woodwork..was a hook from which a bird-cage must have hung. J. Fowles There must been about a dozen.
IV. As pa. t. of branch II.
Was obliged, had to; it was necessary that (I, he, it, etc.) should; (now colloq.) it foolishly happened that (I, he, it, etc.) did. Now only in indirect narration or virtual indirect narration reporting a reflection made at the time, and in conditional clauses. L17.
W. Cather The Doctor had said the house must be absolutely quiet. R. P. Jhabvala In order to find..spiritual enrichment..they must set off for India.
Phrases: if you must know: used to introduce information provided against the judgement or inclination of the speaker. I must love you and leave you: see LOVE verb 1. I must say I cannot refrain from saying. must needs, needs must: see NEEDS adverb. must not am (is, are) not allowed to, am (is, are) obliged not to. the show must go on: see SHOW noun1. you must know, you must understand you ought to be informed, I would have you know.
Comb.: must-be the inevitable, what is fated to happen; must-have noun & adjective (colloq.) (a) noun an essential or highly desirable item; (b) adjective essential or highly desirable; must-see noun & adjective (a) noun a place, event, or entertainment which is recommended as worth seeing; (b) adjective that is a must-see; that is compelling viewing.