Learn French: Il achète treize croissants pour l'équipe. - He buys thirteen croissants for the team.

Yes! Notice how treize starts with the same letters as trois (three). In French, the numbers 11 through 16 all end in -ze. So, just like three is trois, thirteen is treize.

Why does achète have an accent mark (è) when the base verb acheter does not?

The dictionary form of the verb to buy is acheter, with no accent. But when you conjugate it for il (he), you add the grave accent to get achète. This changes the pronunciation of that middle letter from a soft 'uh' to an open 'eh' sound, making it much easier to say out loud!

Do I pronounce the s at the end of croissants?

No, that s is silent. In French, the plural s at the end of a noun is almost never pronounced. When speaking, you can only tell there is more than one croissant because of the number treize right before it.

Why is it l'équipe instead of la équipe?

The word équipe (team) is a feminine noun, so it normally uses la for the word 'the'. However, because équipe starts with a vowel, the 'a' in la is dropped and replaced with an apostrophe. This makes the words flow together smoothly as l'équipe without a choppy pause in the middle.