In English, an apostrophe usually marks possession or a contraction you could leave out. In French it has one job, and it is not optional: it shows that a short word has lost its final vowel because the next word starts with a vowel sound. That is called elision.

Once you know which words do it and before which letters, you stop writing le arbre or je aime, and you read French faster as well.

1. What the apostrophe does in French

Two vowels meeting at the edge of two words are awkward to say, so French drops the first one and writes an apostrophe in its place: le + arbre becomes l'arbre, je + aime becomes j'aime.

This is compulsory. Le arbre or je aime is not a style choice, it is a spelling mistake, and a French reader notices it at once. There is no space on either side of the apostrophe: l'école, never l' école.

2. The words that take an apostrophe

Word	Becomes	Example
le, la	l'	l'arbre, l'école, l'hôtel
je, me, te, se	j', m', t', s'	j'aime, je m'appelle, il s'habille
de, ne	d', n'	beaucoup d'amis, je n'ai pas
que	qu'	qu'il, qu'elle, qu'on
ce	c'	c'est, c'était
si	s', only before il and ils	s'il pleut, s'ils viennent

One side effect catches learners out: after l', you can no longer see whether the noun is masculine or feminine. L'arbre is masculine, l'école is feminine. Check the gender with un or une: un arbre, une école. The same goes for the pair c' and s', which sound alike once elided: the guide to ce and se shows how to tell c'est from s'est.

3. Before which letters

Elision happens before a vowel sound: a word starting with a, e, i, o or u, and a word starting with a mute h, which is silent and behaves like a vowel: l'homme, l'heure, j'habite.

Most French words starting with h have a mute h, but not all of them, and nothing in the spelling tells you which. A good dictionary says so for each word, and it is worth checking the first time you meet one.

4. The aspirated h and other exceptions

Some words start with an aspirated h. It is just as silent, but it blocks elision and liaison: le héros, la honte, le haricot, le hasard.

A few words starting with a vowel refuse elision too: le onze, as in le onze novembre, and le oui, as in un oui franc. They are rare, and the list stops there for everyday French.

5. si, lorsque, puisque: the partial cases

Some words elide only in front of certain words:

• si becomes s' only before il and ils: s'il vous plaît, but si elle vient and si on part.
• lorsque, puisque, quoique elide mostly before il, elle, on, un, une: lorsqu'il arrive, puisqu'elle le dit.
• jusque becomes jusqu': jusqu'à demain, jusqu'ici.
• presque and quelque elide in one word each: presqu'île and quelqu'un.

6. Apostrophe mistakes English speakers make

Mistake	Correct	Why
le ami, la amie	l'ami, l'amie	elision is compulsory before a vowel
Marie's livre	le livre de Marie	French has no possessive apostrophe
l' école	l'école	no space around the apostrophe
si il	s'il	si elides before il
s'elle	si elle	si elides only before il and ils
l'héros	le héros	an aspirated h blocks elision

Watch the pair l'a and la as well: il l'a vue (he saw her) and la vue (the view) sound the same. The guide to la, là and l'a sorts the three out.

One line to remember

A short word ending in a vowel (le, la, je, me, te, se, de, ne, que, ce) drops that vowel before another vowel sound, and the apostrophe takes its place. The exceptions are the aspirated h and a couple of words such as onze and oui. The French grammar rules cover each of these words with examples, and Apostrophe· has you write them in dictation until the apostrophe comes on its own.

Frequently asked questions

Is elision optional in French?

No. Before a vowel sound, le arbre or je aime is a spelling mistake. The only exceptions are the aspirated h and a few words such as onze and oui.

Does French use an apostrophe for possession?

No. French has no possessive 's. Marie's book is le livre de Marie.

Why is it l'homme but le héros?

Both h are silent, but the h of homme is mute and behaves like a vowel, while the h of héros is aspirated and blocks elision. You learn which words have an aspirated h one by one.

Does si always become s'?

Only before il and ils: s'il, s'ils. Before elle or on it stays si: si elle vient, si on part.

Is there a space after the apostrophe?

No. The apostrophe sits between the two words with no space: l'école, j'aime, qu'il.

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