Devoir — must, and the obligation verbs
CEFR A1
Devoir means must / to have to. Like vouloir and pouvoir, it is followed straight by an infinitive with nothing in between.
| je dois | nous devons |
|---|---|
| tu dois | vous devez |
| il/elle doit | ils/elles doivent |
"Vous devez vous reposer." — You must rest. "Je dois aller chez le médecin." — I have to go to the doctor.
You now have three ways to express obligation, and they are not interchangeable:
- devoir — personal. Je dois partir. (I must leave.)
- il faut + infinitive — impersonal, one form only. Il faut se reposer. (One must rest.) This is the easiest and the most common in notices.
- l'impératif — a direct order. Reposez-vous !
A doctor uses all three in one consultation, which is why they arrive together.
What this unlocks
Knowing the rule is not the same as producing it.
This page explains the pattern. The track drills it: the point arrives inside a mini-dialogue, then production marked against a CEFR descriptor, then a module test that returns you to your two weakest sessions if you miss it.