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"Not today" is a phrase which is often translated as "hoy no", and "tomorrow" is an adverb which is often translated as "mañana". Learn more about the difference between "not today" and "tomorrow" below.
tomorrow()
An adverb is a word that describes a verb, an adjective, or other adverbs (e.g., to run quickly, very tired).
a. mañana
The students have a math test tomorrow.Los estudiantes tienen un examen de matemáticas mañana.
A noun is a word referring to a person, animal, place, thing, feeling, or idea (e.g., man, dog, house).
3. (the future)