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English definition of “must”

must

modal verb (PROBABLY)    strong /mʌst/ weak /məst/ /məs/
B2 used to show that something is very likely , probable , or certain to be true : Harry's been driving all day - he must be tired . There's no food left - we must have eaten it all. When you got lost in the forest you must have been very frightened . "You must know Frank ." "No, I don't."Concluding and deducing Grammar:MustGrammar:Must: formsGrammar:Must: usesGrammar:Must and have (got) to?Grammar:Must: typical errors
(Definition of must modal verb (PROBABLY) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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