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"Los primeros" is a form of "primero", an adjective which is often translated as "first". "Otro" is an adjective which is often translated as "another". Learn more about the difference between "otro" and "los primeros" below.
otro(
oh
-
troh
)An adjective is a word that describes a noun (e.g., the big dog).
1. (different)
a. another (singular)
A word or phrase that is singular (e.g., el gato).
Pásame otra servilleta.Pass me another napkin.
3. (following)
A pronoun is a word that stands in for a noun (e.g., she).
a. another
Mi vestido está manchado pero mi madre me traerá otro.My dress is stained but my mother will bring me another.
5. (a new one)
b. another one
Ese era tu último cuaderno, ¿te compro otro?That was your last notebook. Should I buy you another one?
primero(
pree
-
meh
-
roh
)An adjective is a word that describes a noun (e.g., the big dog).
1. (position)
a. first
Los países se enumeran en la primera fila de la tabla.The countries are listed in the first row of the table.
2. (in time)
3. (principal)
An adverb is a word that describes a verb, an adjective, or other adverbs (e.g., to run quickly, very tired).
This means that the noun can be masculine or feminine, depending on the gender of the noun it refers to (e.g., el doctor, la doctora).
a. the best
Era el primero en matemáticas en séptimo grado.I was the best in mathematics in seventh grade.