A compact function word for conditions, indirect yes-or-no questions, degree, and replies that reverse a negative, with noun uses for the note B and for stated conditions.
On ne peut pas entrer ? Mais si, la porte est ouverte.
Can't we go in? But yes, the door is open.
Si j'avais le temps, je lirais ce roman.
If I had time, I would read this novel.
Cette salle est si calme.
This room is so quiet.
Ses si cachent une vraie hésitation.
His reservations hide real hesitation.
Similar words
à ce point
certainement
tout à fait
objection
mais oui
fort
condition
si jamais
oui
sauf si
Meanings
Condition or hypothesis
conjunction
grammar
neutral
Introduces a condition, a possible situation, or an unreal hypothesis on which another action depends.
Usage
Use si before the clause that sets the condition, with the French tense pattern chosen by whether the situation is real, possible, or unreal.
Examples
Si tu viens demain, nous partirons tôt.
If you come tomorrow, we will leave early.
Je prendrai le train s'il pleut.
I will take the train if it rains.
Si j'avais le temps, je lirais ce roman.
If I had time, I would read this novel.
Appelle-moi si besoin.
Call me if needed.
Si la porte est fermée, passe par le jardin.
If the door is closed, go through the garden.
Common mistakes
si il is usually contracted before il or ils, and conditional clauses often take the wrong French tense.
Incorrect
Correct
Si il pleut, je reste ici.
S'il pleut, je reste ici.
Si je saurais, je te le dirais.
Si je savais, je te le dirais.
Je viendrai si je peux demain.
Je viendrai demain si je peux.
Similar words
à condition que
au cas où
dans le cas où
pourvu que
si jamais
sauf si
Indirect yes-or-no question
conjunction
grammar
neutral
Introduces an indirect question where the answer would be yes or no, like English if or whether.
Usage
Use si after verbs such as savoir, demander, vérifier, and voir when the clause reports an uncertain yes-or-no question.
Examples
Je ne sais pas si elle viendra.
I do not know whether she will come.
Demande-lui s'il a reçu le message.
Ask him if he received the message.
Vérifie si la porte est fermée.
Check whether the door is closed.
Dites-moi si vous êtes d'accord.
Tell me whether you agree.
On verra si le plan fonctionne.
We will see whether the plan works.
Common mistakes
si is not combined with est-ce que inside an indirect question, and que cannot replace it when the meaning is whether.
Incorrect
Correct
Je demande si est-ce qu'il vient.
Je demande s'il vient.
Je ne sais pas qu'elle viendra.
Je ne sais pas si elle viendra.
Dis-moi que tu viens ou non.
Dis-moi si tu viens ou non.
Similar words
Degree or intensity
adverb
degree
neutral
Marks a high degree, an equality in negative or comparative contexts, or a degree strong enough to bring a result or concession.
Usage
Use si before an adjective or adverb, often with que when the sentence shows a result, comparison, or concession.
Examples
Cette salle est si calme.
This room is so quiet.
Il parlait si doucement que personne ne l'entendait.
He was speaking so softly that no one could hear him.
Ne cours pas si vite.
Do not run so fast.
Si petit qu'il soit, ce détail compte.
However small it may be, this detail matters.
Je n'avais jamais vu un ciel si clair.
I had never seen a sky so clear.
Common mistakes
si très doubles the intensifier, and si does not normally stand directly before a plain noun.
Incorrect
Correct
Il est si très fatigué.
Il est si fatigué.
C'est si un problème.
C'est un si gros problème.
Il parle si vite comme son frère.
Il parle aussi vite que son frère.
Similar words
tellement
tant
aussi
très
fort
à ce point
Yes after a negative
adverb
conversation
neutral
Answers yes to a negative question or denies a negative statement by affirming the opposite.
Usage
Use si when the prompt is negative and the reply needs to contradict it, reserving oui for ordinary yes answers.
Examples
Tu n'as pas faim ? Si, j'ai faim.
Aren't you hungry? Yes, I am hungry.
Elle ne vient pas ? Si, elle arrive.
Isn't she coming? Yes, she is arriving.
Vous n'avez rien compris ? Si, nous avons compris.
Didn't you understand anything? Yes, we understood.
Il n'aime pas ce livre ? Si, il l'adore.
Doesn't he like this book? Yes, he loves it.
On ne peut pas entrer ? Mais si, la porte est ouverte.
Can't we go in? But yes, the door is open.
Common mistakes
si is often used where oui belongs, or oui is used where French needs si to overturn a negative.
Incorrect
Correct
Tu viens ? Si.
Tu viens ? Oui.
Tu n'es pas prêt ? Oui, je suis prêt.
Tu n'es pas prêt ? Si, je suis prêt.
Il ne part pas ? Non, il part.
Il ne part pas ? Si, il part.
Similar words
oui
mais oui
bien sûr que si
effectivement
certainement
tout à fait
Musical note B
noun
music
neutral
Names the seventh note of the do scale and the written sign or key built on that note.
Usage
Use si for the French solfège note that corresponds to B in English-language note names.
Examples
Le si naturel se trouve juste avant le do.
The natural B comes just before C.
Elle a chanté un si très juste.
She sang a very accurate B.
Cette mesure commence par un si bémol.
This measure begins with a B-flat.
Le morceau passe en si mineur.
The piece moves into B minor.
Accorde la corde sur le si.
Tune the string to B.
Common mistakes
B is not the French note name in solfège, and si is the seventh note of the do scale, not the first.
Incorrect
Correct
Joue un B bémol.
Joue un si bémol.
Le si est la première note de la gamme de do.
Le si est la septième note de la gamme de do.
La messe en B mineur de Bach.
La messe en si mineur de Bach.
Similar words
A condition or reservation
noun
conversation
informal
Names a stated condition, reservation, or imagined possibility, especially when someone keeps raising obstacles.
Usage
Use si as an invariable masculine noun, often in the plural phrase des si et des mais, for conditions and objections.
Examples
Avec des si, on refait le monde.
With ifs, one can remake the world.
Il ajoute toujours des si à sa promesse.
He always adds conditions to his promise.
Ce contrat contient trop de si.
This contract contains too many ifs.
Arrêtons les si et décidons.
Let us stop the ifs and decide.
Ses si cachent une vraie hésitation.
His reservations hide real hesitation.
Common mistakes
des sis adds a plural ending that the noun does not take, and the musical noun is a separate sense.
Incorrect
Correct
Il y a trop de sis dans ce contrat.
Il y a trop de si dans ce contrat.
Avec les si, on refait le monde.
Avec des si, on refait le monde.
Un si bémol dans ce contrat.
Un si dans ce contrat.
Similar words
condition
hypothèse
supposition
réserve
objection
restriction
Usage
Read the surrounding grammar before translating si, since condition, whether, so, yes-after-negative, and the noun senses behave differently.
Common mistakes
si il should normally become s'il, and si is often confused with oui, tellement, or English note names.
Etymology
The conditional conjunction continues Latin si, meaning if. The degree and affirmative adverb comes from Latin sic, meaning thus. The musical noun was formed from the initials of Sancte Iohannes in the hymn used for medieval solfège.
FAQ
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