They do not talke a suffix (ing-ed)They are followed by a bare infinitive,except for ought toThey go before the subject in questions and are followed by not in negationsModal verbs do not usually have tenses. They can refer to the present or the future

Modal Verbs Part 1

Ability: Can, Could, Be able to Obligation/Duty/Necessity: Must, Have to, Should/Ought-Need Absence of Necessity: Needn’t, Don’t have to,Don´t need to, Didn´t need to-Needn´t have done Prohibition: Mustn´t and Can´t Logical Assumptions: Must, Can´t/ Couldn´t Probability: Should and Ought Possibility: Can-Could/May-Might Permission: Can/Could/May/Might Requests: Can/Could/Will/Would/May/Might Offers: I’ll/ Shall/Can/Could Suggestions: Shall/Can/Could Advice: Should/ Ought/Must Criticism: Should/ Ought

Modal Verbs Part 2

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