Devoir is one of the most overloaded verbs in French. In a single sentence, the choice of tense can flip its meaning from I have to to I'm supposed to to I had to and did to I should to I should have. English splits this work across half a dozen modal verbs and constructions (must, have to, was supposed to, should, should have), but French routes everything through devoir and uses tense alone to do the discriminating. Once you internalize the tense-to-meaning map, you stop translating word-for-word from English and start thinking in French aspect.
This page covers the five tenses of devoir that every B1 learner needs in active production. Each section gives you the form, the meanings (usually more than one), and the natural-sounding contexts in which native speakers reach for that tense.
Why devoir behaves this way
Devoir is fundamentally a verb of obligation or expected outcome. Tense shifts the relationship between the obligation and reality:
- Présent — obligation right now, or a current strong inference about reality
- Imparfait — obligation as an enduring state, often unfulfilled
- Passé composé — obligation that resolved into a completed action
- Conditionnel — softened or counterfactual obligation (should)
- Conditionnel passé — counterfactual past obligation (should have)
The verb's meaning isn't really changing — what changes is whether the obligation is happening now, was holding as a background state, was carried out, is recommended hypothetically, or was missed. That framing tells you which tense to grab.
Présent: must, have to, probably is
The présent of devoir does two distinct jobs that English keeps in separate boxes.
Job 1: present obligation
This is the textbook meaning. Something must be done right now, or as a general standing requirement.
| Pronoun | Présent |
|---|---|
| je | dois |
| tu | dois |
| il/elle/on | doit |
| nous | devons |
| vous | devez |
| ils/elles | doivent |
Je dois rappeler ma mère avant ce soir, sinon elle va s'inquiéter.
I have to call my mother back before tonight, otherwise she'll worry.
Tu dois absolument goûter ce fromage.
You really have to try this cheese.
On doit présenter une pièce d'identité à l'entrée.
You have to show ID at the entrance.
Job 2: strong probability (must be / probably is)
This is where English speakers regularly slip. Devoir in the présent + an infinitive also means probably is or must be in the sense of strong inference — exactly like English must. The trap is that English splits must (deduction) from must (obligation), but it uses the same word, so learners forget that French keeps the same verb too.
Il doit être malade — ça fait trois jours qu'on ne l'a pas vu.
He must be sick — we haven't seen him in three days.
Tu dois avoir faim après ce trajet.
You must be hungry after that journey.
Ça doit coûter une fortune, un appart pareil dans le 6e.
An apartment like that in the 6th must cost a fortune.
Context tells you which reading is intended. Je dois partir before lunch is obligation; il doit pleuvoir à Bordeaux en ce moment (judging from the radar) is inference.
Imparfait: was supposed to, had to (background state)
The imparfait je devais, tu devais, il devait, nous devions, vous deviez, ils devaient puts the obligation into a past background, without telling you whether it was carried out. This is its diagnostic feature. Je devais partir à six heures tells you the plan was to leave at six — and leaves entirely open whether you actually did.
Je devais voir Pierre samedi, mais il a annulé au dernier moment.
I was supposed to see Pierre on Saturday, but he canceled at the last minute.
On devait dîner chez mes parents, finalement on est restés à la maison.
We were supposed to have dinner at my parents', in the end we stayed home.
Elle devait passer me prendre à huit heures.
She was supposed to come pick me up at eight.
The imparfait of devoir is the natural French equivalent of English was/were supposed to. English speakers who haven't internalized this often translate was supposed to with awkward periphrases (j'étais supposé…) — that's a calque and sounds wrong. Use je devais.
A second imparfait reading is had to as an enduring requirement during some past stretch — typically with a habitual or descriptive feel:
Quand j'habitais à la campagne, je devais prendre la voiture pour acheter du pain.
When I lived in the countryside, I had to take the car just to buy bread.
Passé composé: had to and did
The passé composé j'ai dû, tu as dû, il/elle a dû, nous avons dû, vous avez dû, ils/elles ont dû (note the circumflex on dû in the masculine singular, dropped in the feminine due and plurals dus, dues) reports an obligation that was actually carried out as a discrete event. This is the contrast with the imparfait that English glosses over.
J'ai dû partir tôt à cause d'un imprévu.
I had to leave early because of an unexpected problem. (and I did leave)
On a dû appeler un serrurier — j'avais oublié les clés à l'intérieur.
We had to call a locksmith — I'd left the keys inside.
Elle a dû refaire tout le dossier parce que son ordi a planté.
She had to redo the whole file because her computer crashed.
Compare:
Je devais partir tôt.
I was supposed to leave early. (intention; outcome unknown)
J'ai dû partir tôt.
I had to leave early. (and I did, as a finite event)
This pairing is the highest-yield place to drill the imparfait/passé composé distinction on a single verb. The same pattern holds for vouloir and pouvoir — see choosing/passe-compose-vs-imparfait for the broader system.
Secondary use: must have (past probability)
The passé composé also carries a must have / probably did reading, parallel to the must be reading of the présent.
Il a dû se tromper de train, ça lui ressemble bien.
He must have taken the wrong train, that's just like him.
Tu as dû mal m'entendre — j'ai dit jeudi, pas mardi.
You must have misheard me — I said Thursday, not Tuesday.
Native speakers reach for this all the time when speculating about what happened. Drill it.
Conditionnel: should
The conditionnel présent je devrais, tu devrais, il devrait, nous devrions, vous devriez, ils devraient is how French expresses should — recommendation, advice, mild obligation. This is one tense, one word, where English uses an entire separate modal verb (should). English speakers who haven't yet built the conditional muscle often default to dois here, which produces sentences that sound much more peremptory than intended.
Tu devrais te reposer un peu, tu as l'air épuisé.
You should rest a bit, you look exhausted.
On devrait peut-être réserver, c'est complet en ce moment.
We should probably book, it's full at the moment.
Vous devriez goûter le menu du chef, c'est ce qu'ils font de mieux.
You should try the chef's menu, it's their best dish.
A secondary use: ought to in the sense of expectation about reality. Le train devrait arriver à dix heures = the train ought to arrive at ten (according to the schedule, with implicit hedging).
Le livre devrait être disponible la semaine prochaine.
The book ought to be available next week.
Ça devrait marcher, mais je ne te garantis rien.
It ought to work, but I'm not guaranteeing anything.
Conditionnel passé: should have
The conditionnel passé combines the conditional of the auxiliary avoir with the past participle dû: j'aurais dû, tu aurais dû, il/elle aurait dû, nous aurions dû, vous auriez dû, ils/elles auraient dû. It means should have — the obligation was not met, and the speaker is expressing regret, reproach, or after-the-fact judgment.
J'aurais dû t'écouter, tu avais raison depuis le début.
I should have listened to you, you were right from the start.
Tu aurais dû me prévenir que tu serais en retard.
You should have warned me that you'd be late.
On aurait dû prendre le train de huit heures, on serait déjà arrivés.
We should have taken the eight o'clock train, we'd already be there.
This construction is the workhorse of regret and reproach in French. J'aurais dû is the verb of every breakup conversation, every Monday-morning quarterback, every moment of looking back at a bad call. Learn it cold.
The dedicated page verbs/conditional/conditionnel-passe-regret drills this further.
The five tenses on one verb: a worked example
Here is the same situation — leaving early — coded in each tense to highlight the differences:
| Tense | Form | Meaning |
|---|---|---|
| présent | Je dois partir tôt. | I have to leave early. / I must be leaving early (inference about a plan). |
| imparfait | Je devais partir tôt. | I was supposed to leave early. (outcome unstated) |
| passé composé | J'ai dû partir tôt. | I had to leave early. (and I did) / I must have left early. |
| conditionnel | Je devrais partir tôt. | I should leave early. (advice/intent) |
| conditionnel passé | J'aurais dû partir tôt. | I should have left early. (but I didn't — regret) |
Walk that table top to bottom and notice how much information French packs into the verb form alone. English needs different modals (have to, was supposed to, had to, should, should have) to do the same work that French does by inflecting devoir.
Side trip: the past participle dû
The past participle dû is one of the few past participles in French that carries a circumflex in the masculine singular, to distinguish it from the partitive article du. The feminine and plurals drop the circumflex: due, dus, dues. This matters for written French; in speech they all sound identical.
J'ai dû refaire la déclaration. (m.sg., with circumflex)
I had to redo the declaration.
Elle a dû refaire la déclaration. (still 'dû' — auxiliary avoir, no agreement with subject)
She had to redo the declaration.
La somme due à l'administration a été réglée.
The amount owed to the administration has been settled. (feminine, no circumflex)
Note that with avoir as auxiliary, the participle doesn't agree with the subject — so elle a dû stays dû, not due. The feminine due appears when the participle behaves like an adjective on its own (the amount owed).
Common Mistakes
❌ J'étais supposé partir à six heures.
Incorrect — calque of English 'I was supposed to'; sounds translated.
✅ Je devais partir à six heures.
I was supposed to leave at six.
❌ Tu dois te reposer un peu, tu as l'air épuisé.
Acceptable but bossy — sounds like a command. For advice, use the conditional.
✅ Tu devrais te reposer un peu, tu as l'air épuisé.
You should rest a bit, you look exhausted.
❌ J'ai dû t'écouter. (intending 'I should have listened to you')
Incorrect — 'j'ai dû' means 'I had to (and did).' For 'should have,' use the conditionnel passé.
✅ J'aurais dû t'écouter.
I should have listened to you.
❌ Je devais partir tôt, alors je suis parti à cinq heures.
Mismatched — 'je devais' leaves the outcome open; if you actually left, the passé composé is more natural for the event.
✅ J'ai dû partir tôt, alors je suis parti à cinq heures.
I had to leave early, so I left at five.
❌ Il doit avoir oublié — il aurait déjà appelé. (intending past inference)
Tense mismatch — for 'he must have forgotten' use the passé composé of devoir.
✅ Il a dû oublier — il aurait déjà appelé sinon.
He must have forgotten — he'd have called by now otherwise.
Key takeaways
- Devoir is the single French verb that covers English must, have to, was supposed to, had to, should, and should have. Tense does the work that English spreads across multiple modals.
- The two pairings that English speakers most often get wrong are: devais (was supposed to, outcome open) vs ai dû (had to and did), and dois (have to, firm) vs devrais (should, advice).
- All tenses of devoir can carry a probability reading in parallel to the obligation reading: il doit être malade (he must be sick), il a dû se tromper (he must have made a mistake), il devait être tard (it must have been late, in narration).
- For regret and missed obligations, j'aurais dû
- infinitive is the universal construction. It is the verb of looking back.
Now practice French
Reading grammar gets you part of the way. The exercises are where it sticks — free, no signup needed.
Start learning French→Related Topics
- Devoir: Obligation, Probability, OwingA2 — Devoir is the most semantically loaded French modal — it covers must, have to, should, ought, be supposed to, and owe. The same surface form il doit étudier can mean obligation, inference, or schedule depending on context.
- Devoir: Full Verb ReferenceA1 — Devoir is the verb of obligation, deduction, and debt — must, have to, should, ought, owe. The conditional je devrais is the standard French equivalent of should, and the conditionnel passé j'aurais dû is the only natural way to say should have. This page is the full reference: every paradigm, every compound tense, the core uses, and the idioms.
- Les Verbes Modaux: Overview of French Modal VerbsA2 — French has four core modal verbs — pouvoir, vouloir, devoir, savoir — plus the impersonal falloir. Each takes a bare infinitive (no preposition), each is highly irregular in conjugation, and each shifts politely into the conditionnel.
- Devrais: How to Say 'Should' in FrenchA2 — There is no separate French word for 'should' — the conditionnel of devoir does the entire job. Learn how tu devrais softens advice, why it replaces tu dois in adult speech, and how to say 'should have' with aurais dû.
- Conditionnel Passé for Regret and ReproachB1 — The modal triplet aurais dû, aurais pu, aurais voulu — French's standard way to express what someone should have, could have, or would have wanted to do. Learn when each one fits, and how to layer them with si seulement and à ta place.
- Passé Composé vs ImparfaitA2 — The central French past-tense decision. Passé composé reports completed events; imparfait paints background, ongoing states, and habits. Mastering the distinction means learning to think of the past as a film in which the camera either holds steady (imparfait) or cuts (passé composé).