LUIS GERARDO VILLAFAÑA CANTÚ Tense auxiliaries TENSE AUXILIARIES & MODAL AUXILIARIES modal auxiliaries Present Simple: do/does Past Simple: did Present Continuous: am/is/are Past Continuous: was/were Present Perfect: have/has Past Perfect: had Present Perfect Continuous: have/has been Past Perfect Continuous: had been Future Simple: will Future Continuous: will be Future Perfect: will have Future Perfect Continuous: will have been Can: ability, possibility, permission Could: past ability, possibility, permission May: possibility, permission Might: possibility, permission, uncertainty Must: necessity, obligation Shall: suggestion, future action (in some dialects) Should: recommendation, obligation Will: future action, intention, willingness Would: hypotheticals, polite requests Ought to: moral obligation, recommendation Need to: necessity, requirement Have to: necessity, obligation