"devoir faire qqch" is usually translated to "must" / "have to". In English, both verbs mean the same in the affirmative, but not in the negative. Example:

  • I must not work
  • I don't have to work.

The first expresses an obligation of "not working", the second expresses a non-obligation of "working". Does "devoir ne pas faire qqch" mean only the former? And if so, how to express the second meaning? Maybe "n'être pas obligé de faire qqch"?

2 Answers 2


In French, to say « Je ne dois pas travailler. » is usually understood thanks to the context. But I usually hear/use it to say: « I don't have to work. ». For example: "Aujourd'hui c'est dimanche, je ne dois pas travailler."

For the other meaning, it's usually better to say: "Je ne PEUX pas travailler. Example. « Je ne peux pas travailler car mon médecin me l'a interdit. ».

Other sentences with the same meaning as « I don't have to work. »

  • Je n'ai pas à travailler.
  • Je n'ai pas besoin de travailler.
  • Je ne suis pas obligé de travailler.
  • 5
    Je n'ai pas à … *“ has a different meaning from “*je n'ai pas besoin de …” and «“je ne suis pas obligé de …”. “Ne pas avoir à” usually denotes an absence of moral obligation which is almost strong enough to be an interdiction. “Je n'ai pas à travailler” doesn't mean “it's forbidden for me to work”, but it doesn't exactly mean ”I have no obligation to work“ either. It's closer to “I don't have to work and you can't make me”. Commented Jul 23, 2019 at 7:05
  • This usage of "je ne peux pas travailler" is very different from English. In English, you would only use "cannot work" if you are physically/psychologically unable to work, eg "I cannot work because I am sick", not with an obligation imposed by someone else, eg "You cannot work after working hours" ("You must not" is used instead). Commented Jul 25, 2019 at 17:22

There are really two forms to keep in mind as pertains to the verb devoir; notice that you do not negate modal verbs in English, whereas you do negate the corresponding verbs in French.


(a) devoir ne pas faire qqc: obligation de ne pas faire (être, faire, laisser, omettre, differer, tarder)

(b) ne pas devoir faire qqc: absence d'obligation de faire (être, faire)

The form you retain is "(a)"; it is not proper to express "must not do" as "must not do" is taken as "having no obligation to do"; it is the right form when "must not do" means "having the obligation not to", which is the sense you give to "must" in "I must not work", sense that must then correspond to A below.

  • A      I must not work overtime; it's forbidden by law. (obligation not to _ Je dois ne pas travailler en heures supplémentaires. (a) not commonly used
    Again, the form "Je ne dois pas travailler en heures supplémentaires" (b) is used, or, apparently better, "Je ne peux pas travailler en heures supplémentaires."

In conclusion, the form you retain is applicable in this strict sense of "must", but it is not as commonly used as the form (b), or the better form using "pouvoir".


The second meaning is then also translated by (b), but as well by other forms;

  • Je ne dois pas travailler. (b) (acceptable)
  • Je n'ai pas à travailler. (best)
  • Je ne suis pas obligé de travailler. (best)
  • Il ne faut pas que je travaille. (not too good)
  • 2
    « Devoir ne pas … » est très rare. On dit beaucoup plus souvent « ne pas devoir … » dans le sens d'une interdiction. L'exemple des heures supplémentaires n'est pas du tout idiomatique, on dirait « je ne dois pas faire d'heures supplémentaires » (ambigü sans contexte : cela peut être une non-obligation ou une interdiction) ou « je ne suis pas obligé de faires des heures supplémentaires » (non-obligation) ou « je ne peux pas faire d'heures supplémentaires » (incapacité ou interdiction) ou autres variantes. Commented Jul 23, 2019 at 7:01
  • @Gilles C'est ce que j'affirme : « not commonly used ».
    – LPH
    Commented Jul 23, 2019 at 9:34

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.