03 Aug 2015 Home » Grammar » Uses of Must and Can’t Uses of Must and Can’t Posted in Grammar By englishlearn_admin On August 3, 2015 Uses of Must and Can’t; You can use must to say that you believe something is certain. You can use can’t to say that you believe something is not possible. Tags:gammar, uses of can't, uses of must Related Posts The Present Simple Tense – Detailed Expression What’s the Difference Between “few” and “a few”? Past Continuous – Detailed Expression and Examples