Common French homophones
a/à, ou/où, ce/se, ces/ses: the substitution-word trick that stops these classic French spelling mix-ups for good.
a / à
- a = the verb "avoir" (to have), can be replaced with "avait" (had): Il a raison (He is right).
- à = a preposition ("to"/"at"), never replaceable with "avait": Je vais à Paris (I'm going to Paris).
ou / où
- ou = "or", a choice, replaceable with "ou bien": Thé ou café ? (Tea or coffee?)
- où = "where", place or time: La ville où j'habite (The city where I live).
ce / se
- ce = determiner (before a noun) or demonstrative pronoun: Ce livre (This book) / C'est vrai (It's true).
- se = reflexive pronoun (before a verb): Il se lave (He washes himself).
ces / ses
- ces = plural demonstrative "these/those", can be swapped for singular "ce/cette": Ces livres → ce livre.
- ses = plural possessive "his/her", can be swapped for singular "son/sa": Ses amis → son ami.
leur / leurs
- leur, invariable before a verb = the pronoun "them/to them": Je leur parle (I speak to them).
- leur(s) as a possessive determiner agrees with the thing owned: leur maison (their house — one house) / leurs enfants (their children — several).
Quick method: mentally swap in a test word ("avait" for a/à, "ce livre" for ces/ses…). If the substitution still makes sense, you've got the right spelling.
quand / quant / qu'en
- quand = "when" (time), can be replaced with "lorsque": Il viendra quand il pourra (He'll come when he can).
- quant (à) = "as for", always followed by "à/au/aux": Quant à moi, je reste (As for me, I'm staying).
- qu'en = "que" + "en": Je ne pense pas qu'en faisant cela... (I don't think that by doing this...).
sans / s'en / sens
- sans = preposition, "without": Il part sans bagage (He leaves without luggage).
- s'en = "se" + "en" before a verb: Il s'en va (He's leaving).
- sens = noun ("direction"/"meaning") or the verb "to feel": Le bon sens (common sense).
Frequently asked questions
How do I stop confusing "on" and "on n'"?
Before a negation, "on" elides to "on n'": "On n'a rien vu" (we didn't see anything). Writing "on a rien vu" without the "n'" is an incomplete negation, only acceptable in speech.
How are "quelque" and "quel que" different?
"Quelque" (one word) is an adjective or adverb: "quelques amis" (a few friends), "quelque peu surpris" (somewhat surprised). "Quel que" (two words) always precedes "soit/soient" and agrees: "quels que soient les résultats" (whatever the results).
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