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"Firmado" is a form of "firmar", a transitive verb which is often translated as "to sign". "Sellado" is a form of "sellado", an adjective which is often translated as "sealed". Learn more about the difference between "firmado" and "sellado" below.
firmar()
A transitive verb is a verb that requires a direct object (e.g., I bought a book.).
a. to sign
Hoy, el dueño y el inquilino firmarán el contrato de arrendamiento.Today, the owner and the tenant will sign the lease agreement.
An intransitive verb is one that does not require a direct object (e.g., The man sneezed.).
sellado()
An adjective is a word that describes a noun (e.g., the big dog).
1. (franked)
a. sealed (official document)
Necesito que el expediente académico esté sellado por la universidad.I need my academic record to be sealed by the university.
b. stamped (passport, letter)
Las páginas selladas del pasaporte me recuerdan los países donde he viajado.The stamped pages in my passport remind me of all the countries I have been to.
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
a. sealing (official document)
El consejo realizará el sellado del documento oficial con las propuestas mañana.The council is in charge of the sealing of the proposal's official documents tomorrow.
b. stamping (passport, letter)
El sellado de cartas se realiza en la oficina de correos.Letter stamping occurs at the post office.
