vs
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"Antes" is a form of "antes", an adverb which is often translated as "before". "Desde hace" is a phrase which is often translated as "for". Learn more about the difference between "desde hace" and "antes" below.
desde hace( 
dehs
-
deh
ah
-
seh
)A phrase is a group of words commonly used together (e.g., once upon a time).
antes(
ahn
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tehs
)An adverb is a word that describes a verb, an adjective, or other adverbs (e.g., to run quickly, very tired).
1. (time)
2. (location)
a. before 
Descubrí quién era el asesino diez páginas antes del final.I discovered who the murderer was ten pages before the end.
Me bajo una parada antes que la tuya.I get off one stop before yours.
A conjunction is a word that connects words, phrases, clauses, or sentences (e.g., The cat and the dog slept.).
3. (preference)
An adjective is a word that describes a noun (e.g., the big dog).
4. (precedent)
a. before 
Tenemos que preparar la reunión el día antes.We have to prepare the meeting the day before.