Réponse:
EXO 1:
a. obligation
b.possibilité
c.capacité
d. interdiction
EXO 2:
a. Any GoT fan must watch all the seasons
.... must have watched all the seasons
b.At school, i musn't use my cellphone
At school, I could not use my cellphone
c. After watching the pilot of this new series I think I may have a headache
After having watched the pilot, i think may have had a headache.
d. Josh is so addicted! He can stay in front of the TV for hours.
Josh was so addicted! He could have stayed in front of the TV for hours