Plural of compound nouns
In a compound noun, only nouns and adjectives can take the plural marker. Verbs, adverbs and prepositions stay the same.
Examples
Des grands-mères.
Key word(s): grands-mères
Adjective "grand" plus noun "mère": both agree.
Des arcs-en-ciel.
Key word(s): arcs-en-ciel
"Arc" (noun) agrees. "En" (preposition) and "ciel" stay the same.
Des porte-monnaie.
Key word(s): porte-monnaie
"Porte" (verb) is invariable, plus "monnaie" (you carry money, logically singular).
Des timbres-poste.
Key word(s): timbres-poste
"Timbre" (noun) agrees. "Poste" stays singular (= for the post).
Des chefs-d'oeuvre.
Key word(s): chefs-d'oeuvre
"Chef" (noun) agrees. "D'oeuvre" (preposition plus noun) is invariable.
Common mistakes
- Making the verb agree in a compound noun ("des portes-monnaie")
- Forgetting to make both words agree when they are two nouns
- Hesitating over the logical meaning (a porte-monnaie carries money)
Test yourself
Des ___.
Des ___.
Des ___.
Tips to remember
- Analyze each word: noun? adjective? verb? preposition?
- Only nouns and adjectives take the plural.
- When in doubt, think about the logical meaning of the compound word.
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