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"La" is a definite article which is often translated as "the", and "temprano" is an adverb which is often translated as "early". Learn more about the difference between "la" and "temprano" below.
la(
lah
)A definite article is a word that identifies a noun as specific or known to the speaker (e.g., the girl).
a. the 
La pelota está en el tejado.The ball is on the roof.
La leche está en el refrigerador.The milk is in the refrigerator.
A pronoun is a word that stands in for a noun (e.g., she).
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
temprano(
tehm
-
prah
-
noh
)An adverb is a word that describes a verb, an adjective, or other adverbs (e.g., to run quickly, very tired).
An adjective is a word that describes a noun (e.g., the big dog).