The French Subjunctive After Necessity and Will
If you have learned how to build the present subjunctive on the formation page, this is where you learn the first reason to actually use it. The subjunctive never appears on its own; something has to trigger it. The easiest and most common trigger group is necessity and will - the language of must, want, demand and wish. Start here, because these expressions turn up in nearly every conversation and the logic behind them carries over to the harder triggers later.
The thread running through the whole group is this: necessity and will describe things that are not yet real. When you say you want someone to leave, they have not left. When you say something must happen, it has not happened. French marks that unreal, willed quality with the subjunctive. Plain statements of fact stay in the indicative; wanted, required and demanded things go to the subjunctive.
il faut que: the workhorse
means "it is necessary that" and is the single most common subjunctive trigger in French. Name the person who has to act, and the verb after goes subjunctive:
- . (You must leave. / You have to leave.)
- attention. (We must be careful.)
- à l'. (You must be on time.)
- ' son . (She has to finish her work.)
Note , , , - all subjunctive, and , pulling out their irregular forms from the formation page.
If you do not name a specific person, takes a plain infinitive and there is no subjunctive at all:
- . (We need to leave. / One must leave.)
- attention. (One must be careful.)
That contrast - versus - is the different-subject rule in miniature, and it governs the entire group.
The different-subject rule
This is the rule to engrave. It decides infinitive versus subjunctive for every verb on this page.
- Same subject on both verbs -> infinitive, no .
- Different subjects -> + subjunctive.
Watch it with :
- . (I want to leave.) - I want, I leave: one subject, so infinitive.
- . (I want you to leave.) - I want, you leave: two subjects, so + subjunctive.
English hides this: "I want to leave" and "I want you to leave" look structurally similar. French treats them as two completely different builds. You can never say "je veux que je parte" - if the subject is the same, the infinitive is compulsory.
| English | Subjects | French build |
|---|---|---|
| I want to leave | I / I | je veux |
| I want you to leave | I / you | je veux |
| She wants to come | she / she | elle veut |
| She wants us to come | she / we | elle veut |
vouloir, souhaiter, exiger, demander: verbs of will
A cluster of verbs expressing wanting, wishing and demanding all behave like . With a different subject they take + subjunctive:
- . (I want you to come.)
- . (She wishes us to be happy.)
- devoirs. (The teacher demands that the pupils do their homework.)
- . (He asks that you wait here.)
- . (We wish for everything to go well.)
Common members of the set: , (to wish), (to desire), (to demand), (to ask), (to order), (to prefer). All of them describe an act of will aimed at someone else, which is why the different-subject clause goes subjunctive.
A note on irregular forms: when the second verb is , , , , and the like, it takes its irregular subjunctive - , , , ' . If any of those look unfamiliar, the full tables are on the formation page.
il vaut mieux que, il est nécessaire que, il est important que
Impersonal expressions of necessity and advisability behave like - with a named subject after , the verb is subjunctive:
- . (It is better that you stay here.)
- partions . (It is necessary that we leave early.)
- important . (It is important that you understand the rule.)
- ' . (It is essential that she knows the truth.)
And again, with no specific subject these revert to + infinitive: (it is better to leave), important (it is important to understand). Same different-subject logic, every time.
A quick contrast: certainty takes the indicative
To stop the subjunctive spreading where it does not belong, hold one contrast in mind. Necessity and will are unreal, so they take the subjunctive. Certainty is factual, so it takes the indicative:
- ' . (I want him to come.) - will -> subjunctive .
- ' . (I know he is coming.) - certainty -> indicative .
Verbs like , (affirmative), certain and state facts and stay in the indicative. The detail of doubt, opinion and the negative-and-question flips belongs to a later page; for now, just note that necessity and will trigger the subjunctive, plain certainty does not.
Worked examples
- devoirs. (You have to do your homework.) - il faut que + irregular .
- à . (I want you to be ready at eight.) - vouloir que + irregular .
- . (She wishes us to come with her.) - souhaiter que + two-stem .
- arrive à l'. (The boss demands everyone arrive on time.) - exiger que + regular .
- partions . (It is better that we leave now.) - il vaut mieux que + .
- important ' . (It is important that he goes to the doctor.) - il est important que + irregular .
- . (I want to leave early.) - same subject, so infinitive, no subjunctive.
Common mistakes English speakers make
The classic error is breaking the different-subject rule: French speakers never say "je veux que je parte" - if the subject is the same, you must use the infinitive, . Conversely, do not smuggle an infinitive in where the subjects differ: "je veux toi partir" is not French; it has to be . Another trap is leaving the second verb in the indicative after a trigger - it is , not "il faut que tu pars". Watch the irregulars too: "il faut que tu es" is wrong; goes subjunctive, . Learners also over-apply the rule, putting a subjunctive after verbs of certainty - ' , not "qu'il vienne", because thinking something is true is a statement of fact. Finally, remember that the bare impersonal forms drop the subjunctive entirely: and important use the infinitive because no specific subject is named.
See also
- The present subjunctive formation page covers how to build every form, including the irregulars (être, avoir, aller, faire, vouloir) used throughout this page.
- The impersonal verbs page covers il faut and the other il-constructions in more detail.
- The intermediate French grammar page sets the subjunctive triggers in the wider B1-B2 picture.
- The French grammar cheatsheet covers the whole A1-B2 grammar map at a glance.