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"Guardilla" is a noun which is often translated as "attic", and "desván" is a noun which is also often translated as "attic". Learn more about the difference between "guardilla" and "desván" below.
la guardilla()
A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).
el desván()
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).