Elision
The sequence "vowel + vowel" is rare in French (especially between words). As such, determiners that end in a vowel change their form if the noun that follows begins with a vowel, e.g.:
- le > l', e.g.: l'automne
- la > l'a, e.g.: l'importance
- ma > mon, e.g.: mon importance
- ta > ton, e.g.: ton importance
- sa > son, e.g.: son importance
- ce > cet, e.g.: cet automne
This phenomenon is known as elision. This also happens with words that begin with what is referred to as "h muet" (silent "h"), e.g.:
- l'homme [lɔm] , l'hiver [livɛʁ] , l'horizon, l'hôtel, l'habitude
Still, within the category of words that begin with silent "h", you need to distinguish between those that result in elision ("h" muet words) and the rest ("h" aspiré words), where the "h" is still silent, but elision and liaison are blocked, for historical reasons. Here are the most common words of this latter type:
- le hibou , le homard , le héros , la honte , la hache , le hasard, le haut, le hockey, le hameau, la haine, la hanche, le handicap, le hachoir, le hérisson, le hoquet, la hiérarchie, la Hollande, le hamburger, le hamster, le héron, le hamac, le hongrois, le hangar, le harcèlement, le houblon
Note that "h" aspiré words don't actually involve any aspiration! (they just block elision and liaison; nothing is pronounced).
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)
- use l' before a vowel, e.g.: l'eau and NOT la eau
- the masculine adjective vieux changes to vieil before a vowel, e.g.: un vieil homme.