masculine feminine  
Singular teléfono negro falda roja Adjectives ending with -o form their feminine form with -a.
Plural teléfonos negros faldas rojas
Singular árbol verde blusa verde Adjectives ending with -e or with a consonant have the same form in both genders.
Plural árboles verdes blusas verdes
Singular vestido azul camisa azul
Plural vestidos azules camisas azules

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