Here's a breakdown of its different uses:
1. Obligation/Necessity:
* "Je dois faire mes devoirs." (I have to do my homework.)
* "Tu dois être à l'heure." (You must be on time.)
* "Ils doivent payer leurs dettes." (They have to pay their debts.)
2. Probability:
* "Il doit être fatigué après son voyage." (He must be tired after his trip.)
* "Elle doit avoir faim." (She must be hungry.)
* "Ça doit être difficile." (It must be difficult.)
3. Debt/Owing:
* "Je te dois 10 euros." (I owe you 10 euros.)
* "Il me doit encore de l'argent." (He still owes me money.)
Conjugation of Devoir:
| Person | Present Tense | Past Tense | Future Tense |
|---|---|---|---|
| Je | dois | devais | devrai |
| Tu | dois | devais | devras |
| Il/Elle/On | doit | devait | devra |
| Nous | devons | devions | devrons |
| Vous | devez | deviez | devrez |
| Ils/Elles | doivent | devaient | devront |
Important Note: "Devoir" can also be used as a noun meaning "duty" or "homework".
Let me know if you have any other questions about the verb "devoir"!