This is really hard to understand, maybe I could get some help? :)

In French, adjectives usually come after the noun, and they should agree with the noun they are describing. Agreement means that if a noun is masculine singular ("le"), the adjective describing it must also be masculine singular ("grand"); if the noun is feminine ("la"), the adjective must be as well ("grande"). If the noun is plural ("les"), the adjective should also be plural (grands/grandes). Note: If you're not sure it the plural word masculine or feminine, you'll need to look the word up to verify.​