Invariable adjectivesIn Spanish there are groups of adjectives that remain the same for both masculine and feminine singular, i.e they don't follow the general rule for endings -o (masculine) and -a (feminine).
Although among these adjectives we will find some exeptions, we can say that invariable adjectives are those with endings:
-e ( e.g grande, elegante, terrible, elocuente)
-a ( e.g deportista, elitista, rosa, naranja,)
-l ( e.g leal, legal, fiel, cruel)
-z ( e.g feroz, veloz, feliz, capaz)
-n ( e.g joven, común)
-ar (e.g circular, regular)