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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:MustSee moreGrammar:Must: formsSee moreGrammar:Must: usesSee moreGrammar:Must and have (got) to?See moreGrammar:Must: typical errorsSee more
(Definition of must modal verb (PROBABLY) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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