UNIT 1 TIME FOR CHANGE

Modal verbs: must mustn´t , can can´t , should shouldn´t, could couldn´t , may and might.
Semi-modal : have to  don´t have to
                         
Rules: Must/ Mustn´t/ Not allowed
Ability:Can/Can´t / Couldn´t / be able to
Permision:Can? / May...? /Could...?
No obligation: Don´t have to
Necessity: Have to / Nead to
Advice : Should / Shouldn´t / Ought/ Oughtn´t
Possibility: May / Might