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"El martes" is a form of "martes", a noun which is often translated as "Tuesday". "El jueves" is a form of "jueves", a noun which is often translated as "Thursday". Learn more about the difference between "el martes" and "el jueves" below.
el martes(
mahr
-
tehs
)A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
el jueves(
hweh
-
behs
)A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).