Italian adjectives can be singular, plural, masculine or feminine by changing the ending. Adjectives always agree in gender (masculine / feminine) and number (singular / plural) with the nouns they refer to. Don't worry now, we'll see Italian adjectives
in more detail in future lessons.
In the case of adjectives of nationality, there are only two types: one that follows both gender and number, and one that only follows number. When expressing nationalities, Italians do not use capital letters.