Agreement of adjectives

What “adjective agreement” means (the 10‑second idea)

In French, an adjective usually changes to match the noun it describes in:

• gender: masculine / feminine
• number: singular / plural

So you don’t just learn petit. You learn a pattern.

The core pattern: add endings step by step

1. Start with the masculine singular form: petit.

2. Need feminine? Often add -e: petit → petite.

3. Need plural? Often add -s: petit → petits.

4. Feminine plural = combine both: petite → petites.

A fast self-check (use this every time)

• 1) Find the noun: what word is being described?

• 2) Identify the noun’s gender: un = masculine, une = feminine (or learn the noun with its article).

• 3) Identify the noun’s number: singular or plural?

• 4) Choose the adjective form (add -e and/or -s if needed).

Common trap: the adjective can be far from the noun

Agreement depends on the noun, not on distance.

• Correct: Les enfants qui naissent en décembre sont les plus jeunes de l’année.

jeunes is plural because it describes les enfants (plural), even though other words are in between.

Plural spelling: -s is common, but sometimes it’s -x

Some adjectives form the plural with -x (you mainly meet this in very common adjectives).

Practical tip: if you see -eau at the end (like beau), expect -x in the plural: -eau → -eaux.

Two key exceptions you should recognize immediately

• Already ends in -e (masculine) → feminine is often the same.

  Ex: magnifique → magnifique (no added -e)

• Already ends in -s or -x (singular) → plural is often the same.

  Ex: gris → gris ; heureux → heureux

Irregular feminine forms: learn them as pairs

Some very frequent adjectives have a special feminine form. Don’t “apply a rule”; memorize the pair.

Mini checklist before you answer (avoid 90% of mistakes)

• I matched the adjective to the noun (not to what I personally mean).

• If the noun is plural (les / des), my adjective is plural too: usually -s.

• If the noun is feminine (la / une), I checked for -e or an irregular feminine (beau → belle).

• If the adjective ends in -e, I didn’t add an extra -e.

• If the adjective ends in -s or -x, I didn’t add another -s in the plural.

Quick sanity examples (correct vs. common wrong forms)

• les matinées froides (fem. plural) — les matinées froid

• les journées chaudes (fem. plural) — les journées chaud

• ce beau mois (masc. singular) — ce belle mois

• les nouveaux collègues (masc. plural) — les nouveau collègues