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"Cenando" is a form of "cenar", an intransitive verb which is often translated as "to have dinner". "Tu" is a form of "tu", an adjective which is often translated as "your". Learn more about the difference between "cenando" and "tu" below.
cenar()
An intransitive verb is one that does not require a direct object (e.g., The man sneezed.).
a. to have dinner
Vamos a cenar a la casa de mis padres esta noche.We're having dinner at my parents' house tonight.
c. to dine
¿Me pongo el esmoquin para cenar con el conde?Should I wear my tuxedo to dine with the Count?
A transitive verb is a verb that requires a direct object (e.g., I bought a book.).
a. to have for dinner
Voy a cenar un filete buenísimo.I am going to have a delicious steak for dinner.
tu()
An adjective is a word that describes a noun (e.g., the big dog).
1. (informal) (possessive)
A word or phrase used to refer to the second person informal “tú” by their conjugation or implied context (e.g., How are you?).