Indefinite pronouns & adjectives (quelqu'un, quelque chose, chaque, certains...)

Quelqu'un a appelé.Chaque élève a son propre bureau.Certains préfèrent le thé.Someone called.Each student has their own desk.Some people prefer tea.

French has a small family of words for talking about people, things and quantities without naming them exactly — someone, something, each, some, a few, several. Most of them are simple to use once you know whether they're a fixed pronoun, an adjective that needs a noun, or both.

Quick shortcut: quelqu'un/quelque chose never change form; chaque is an adjective only (always needs a noun), its pronoun partner is chacun/chacune; certains/certaines, quelques and plusieurs all describe more than one, and only certains/certaines and quelques-uns/quelques-unes agree in gender.

Quelqu'un and quelque chose: someone, something

Quelqu'un (someone/somebody) and quelque chose (something) are both invariable pronouns — they never change form for gender or number:

• Quelqu'un a appelé pendant que tu étais sorti. (Someone called while you were out.)
• Il y a quelqu'un à la porte. (There's someone at the door.)
• J'ai oublié quelque chose au bureau. (I forgot something at the office.)
• Quelque chose ne va pas. (Something's wrong.)

When an adjective describes what quelqu'un or quelque chose refers to, it's introduced by de and stays in the masculine singular, whatever the adjective would normally agree with:

• J'ai rencontré quelqu'un de gentil. (I met someone nice. — never ❌ gentille, even to describe a woman)
• *Tu as lu **quelque chose d'*intéressant récemment ? (Have you read anything interesting recently?)
• ✅ Il s'est passé quelque chose de beau., never ❌ quelque chose de belle. (the adjective after de never agrees, even when the situation being described would otherwise call for a feminine form)

Chaque vs. chacun/chacune: each

Chaque (each, every) is an adjective only — it always comes directly before a singular noun and never stands alone:

• Chaque élève a son propre bureau. (Each student has their own desk.)
• Il vient chaque semaine. (He comes every week.)

Chacun (masculine) and chacune (feminine) are the corresponding pronouns — they stand alone, without a noun, and agree in gender with whatever they refer to:

• Chacun a son avis sur la question. (Everyone has their own opinion on the matter.)
• Mes sœurs sont toutes différentes : chacune a sa propre personnalité. (My sisters are all different: each one has her own personality.)
• ✅ Chacun son tour !, never ❌ Chaque son tour ! (chaque can't stand alone as a pronoun — that's chacun's job)

Certains/certaines: some, certain ones

Certains (masculine) and certaines (feminine) describe an unspecified part of a larger group — "some" or "certain ones" — and work as both an adjective before a plural noun and a pronoun standing alone:

• Certains jours, je préfère rester à la maison. (Some days, I prefer to stay home. — adjective + noun)
• Certains pensent que c'est une bonne idée. (Some people think it's a good idea. — pronoun, no noun)
• Parmi ses romans, certains sont meilleurs que d'autres. (Among his novels, some are better than others.)

Certain(e) also has a separate singular use, placed before the noun, meaning "a certain" (a specific but unnamed one) rather than "some":

• Il habite dans une certaine rue du centre-ville. (He lives on a certain street downtown.)

Quelques and quelques-uns/quelques-unes vs. plusieurs: a few, several

Quelques is an invariable adjective meaning "a few" — a small, indefinite number. It goes directly before a plural noun and never changes form:

• J'ai quelques questions à te poser. (I have a few questions to ask you.)
• Il reste quelques places. (There are a few seats left.)

Its pronoun counterpart, used without a noun, does agree in gender: quelques-uns (masculine) and quelques-unes (feminine):

• J'ai lu plusieurs de ses livres. Quelques-uns m'ont beaucoup plu. (I've read several of his books. A few of them I liked a lot.)
• Parmi ces photos, quelques-unes sont vraiment réussies. (Among these photos, a few are really good.)

Plusieurs means "several" — a somewhat larger indefinite number than quelques. It's invariable and, unlike quelques, uses the exact same form as both adjective and pronoun — there's no separate plusieurs-uns:

• Plusieurs personnes ont posé la même question. (Several people asked the same question. — adjective)
• J'ai essayé plusieurs solutions. Plusieurs ont fonctionné. (I tried several solutions. Several worked. — pronoun, identical form)

Common mistakes

• ❌ J'ai rencontré quelqu'un de gentille. → ✅ J'ai rencontré quelqu'un de gentil. (the adjective after quelqu'un de / quelque chose de stays masculine singular, never agreeing with the real-world referent)
• ❌ Chaque ont leur propre avis. → ✅ Chacun a son propre avis. (chaque can't stand alone as a pronoun — use chacun/chacune)
• ❌ Certain étudiants sont absents. → ✅ Certains étudiants sont absents. (the plural "some" sense needs the plural form certains/certaines)
• ❌ J'ai lu quelques de ses livres. → ✅ J'ai lu quelques-uns de ses livres. (standing alone as a pronoun needs quelques-uns/quelques-unes, not the adjective quelques)

Quick check

Key takeaways

• Quelqu'un (someone) and quelque chose (something) are invariable pronouns; an adjective after them takes de and stays masculine singular (quelqu'un de gentil, quelque chose de beau).
• Chaque is an adjective only, always with a singular noun; its pronoun counterpart is chacun/chacune, which agrees in gender.
• Certains/certaines ("some/certain ones") work as both adjective and pronoun and agree in gender; the singular certain(e) separately means "a certain [specific but unnamed]."
• Quelques ("a few") is an invariable adjective; its pronoun form quelques-uns/quelques-unes agrees in gender. Plusieurs ("several") is invariable and uses the same form for both adjective and pronoun.