Devoir vs Falloir
Verbs expressing obligation and necessity
By Laura K. Lawless, About.com Guide
The French verbs devoir and falloir can be confusing because they both express obligation and necessity, but in different
ways. In addition, each verb has a different meaning when followed by a noun.
Devoir - When followed by an infinitive, devoir expresses obligation, probability, or supposition.
Je dois partir
I have to, I must, I'm supposed to leave
Je devais étudier
I had to, was supposed to study
Je devrai travailler
I will have to work
Je devrais lire
I would have to, I should read
J'ai dû manger
I had to eat, I must have eaten
J'aurais dû manger
I should have eaten
When followed by a noun, devoir means "to owe."
Je dois 5 dollars
I owe 5 dollars
Je ne lui devais rien
I didn't owe him anything
Devoir - must, to have to; to owe
Simple conjugations for the French verb devoir
Present
Future
Imperfect
Present participle
je
dois
devrai
devais
devant
tu
dois
devras
devais
il
doit
devra
devait
nous
devons
devrons
devions
Auxiliary verb
Passé composé
avoir
vous
devez
devrez
deviez
Past participle
dû (due, dus, dues)
ils
doivent
devront
devaient
Subjunctive
Conditional
Passé simple
je
doive
devrais
dus
Imperfect subjunctive
dusse
tu
doives
devrais
dus
dusses
il
doive
devrait
dut
dût
nous
devions
devrions
dûmes
dussions
vous
deviez
devriez
dûtes
dussiez
ils
doivent
devraient
durent
dussent
(tu)
dois
(nous)
devons
(vous)
devez
Imperative
Verb conjugation pattern
Devoir is an irregular verb
Using devoir
Falloir is stronger and somewhat more formal than devoir; it expresses necessity. Falloir can be used with an infinitive
or the subjunctive. Because it's an impersonal verb, falloir does not conjugate for different subjects, so in order to
specify the person who needs to do something, you can either use the subjunctive or an indirect object pronoun with
the infinitive.
Il faut travailler.
It is necessary to work, One needs to work.
Il me faut travailler, Il faut que je travaille.
I need to work.
Il ne faut pas manger.
One must not eat.
Il nous fallait manger.
We had to eat.
Il ne nous faut pas manger, Il ne faut pas que nous mangions.
We don't need to eat, We mustn't eat
When used with a noun, falloir means "to need."
Qu'est-ce qu'il te faut ?
What do you need?
Il me faut un stylo.
I need a pen.
Falloir - to be necessary
Simple conjugations for the French verb falloir
il
Present
Future
Imperfect
faut que
faudra que
fallait que
Present participle
n/a
Passé composé
il
Auxiliary verb
avoir
Past participle
a fallu que
Subjunctive
Conditional
Passé simple
Imperfect subjunctive
faille que
faudrait que
fallut que
fallût que
Imperative
n/a
Falloir is impersonal and irregular, and is one of the
most common French verbs
Using falloir Expressions with falloir Quiz on falloir
Summary
Devoir
Falloir
Type of verb
personal
impersonal
Register
normal
formal/normal
Meaning when followed by...
infinitive
must, to have to
to be necessary/need to
subjunctive
---
to be necessary/need to
noun
to owe
to need