d'une durée

d'un repère dans le passé

since

for

since

for

since

for

since

for

since

for

since

for

since

for

since

for

since

for

since

for

Pour parler d'un événement passé terminé

Pour parler d'un événement passé qui a un lien avec le présent

Pour faire un bilan au moment où l'on parle

Pour exprimer un événement futur

I haven't been to school for a week.

I haven't been to school since a week.

He has done his homework everyday since last Monday.

He have done his homework everyday since last Monday.