Exprimer l'obligation
Il existe plusieurs façons d'exprimer l'obligation :
Au présent
- Must + base verbale: "You must be quiet!"
- Have to + base verbale: "I have to leave now."
- Have got to + base verbale: "they've got to move their car."
Au futur et au passé
On emploie : will have to / had to.
- "You 'll have to move if you get this job."
- "They had to borrow money to pay for their house."
Attention ! "Mustn't" exprime l'interdiction et non l'absence d'obligation :
"You mustn't make noise" = tu ne dois pas faire de bruit. (C'est interdit.)
Exprimer l'absence d'obligation
Pour exprimer l'absence d'obligation (ce qu'on n'est pas obligé de faire), on utilise :
Au présent
- Don't have to + base verbale: "You don't have to rush. You've got plenty of time."
- Needn't + base verbale: "You needn't rush. You've got plenty of time."
Au futur
- Won't have to + base verbale: "You won't have to get up early, we are leaving at 10."
Au passé
- Didn't have to + base verbale: "I didn't have to pay for the entrance. It was free."
Attention : needn't have + participe passé = tu n'aurais pas dû.
"You needn't have brought me flowers " (= tu m'as apporté des fleurs, mais ce n'était pas nécessaire.)
