Learn French: L'eau est très froide. - The water is very cold.

Froide is the feminine form of the adjective froid (cold). Because the noun it describes, eau (water), is feminine, we must add an e to the end of the adjective to make it match.

Does adding the e to froide change how it sounds?

Yes! In the masculine form froid, the final d is silent. But when you add the e to make the feminine form froide, that d is no longer the last letter, so you must pronounce it.

How can I tell that eau is feminine since it uses l' instead of la?

You can't tell just by looking at l'eau! Because eau starts with a vowel, both masculine le and feminine la shrink to l'. You just have to memorize that eau is a feminine word. The fact that this sentence uses the feminine adjective froide is actually a great clue to help you remember!

Is the s at the end of très pronounced here?