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           What do you know about 'MODALS' ?                              modal ˈverb  ( also  modal )  noun  [ countable ]  technical         one of these  verb   forms : can, could, may, might, shall, should, will, would, must, ought to, used to, need, had  better , and  dare . They are all used with other verbs to  express  ideas such as  possibility ,  permission , or  intention .  From Longman Dictionary of Contemporary English.