Learn French: Il y a une trentaine ou une quarantaine d'arbres dans le parc. - There are about thirty or forty trees in the park.

Il y a une trentaine ou une quarantaine d'arbres dans le parc.

There are about thirty or forty trees in the park.

Breakdown of Il y a une trentaine ou une quarantaine d'arbres dans le parc.

Questions & Answers about Il y a une trentaine ou une quarantaine d'arbres dans le parc.

Are words like trentaine and quarantaine always feminine?

Yes! When you add the -aine suffix to a number to mean 'about X', it becomes a feminine noun. Because it is a noun, it needs an article, which is why we use une here.

Why do we use d'arbres instead of des arbres after these numbers?

Because une trentaine and une quarantaine act as nouns of quantity. Just like you use de after beaucoup (a lot of) or un groupe (a group of), you must use de or d' after an -aine word. You would only use des if you specifically meant 'about thirty OF THE trees'.

How do we change the spelling from trente to trentaine?

For numbers ending in an -e, you drop that final -e before adding the -aine suffix. So trente drops its final letter to become trentaine, and quarante becomes quarantaine.

Wait, doesn't une quarantaine also mean 'a quarantine' in French?

It does! The medical term actually comes from the historical practice of isolating ships for forty days. In modern French, you have to use the context to know whether it means 'about forty' or 'a quarantine'.