Adjective Agreement
In Spanish, Adjectives must agree in Gender and Number with the Nouns they modify:
Notice that in the Spanish phrase EVERYTHING is Plural. That's rule #1. The other rule isn't so easy. In Spanish, nouns have Gender. They are either masculine or feminine. English doesn't have that, but the closest thing would be using a/an.
| Masculine | Feminine | |
| English | A dog* | An apple* | 
| Spanish | Un perro | Una manzana | 
Okay, so Nouns have Gender. But since Adjectives have to Agree in Gender...
| Masculine | Feminine | |
| English | a white dog* | An red apple* | 
| Spanish | Un perro blanco | Una manzana roja | 
Well, alright, I can accept that. But what if you have a situation with both issues at once? Gender AND Number?!
| English | Masculine | Feminine | 
| Singular | a white dog* | An red apple* | 
| Plural | Some white dogs | Some red apples | 
| Spanish | ||
| Singular | Un perro blanco | Una manzana roja | 
| Plural | Unos perros blancos | Unas manzanas rojas | 
Not difficult, just something to keep track of.
*These words aren't really masculine/feminine, but I used them to show you what I mean.