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"En" is a form of "en", a preposition which is often translated as "in". "Tren" is a noun which is often translated as "train". Learn more about the difference between "en" and "tren" below.
en(
ehn
)A preposition is a word that indicates the relationship between a noun and another word (e.g., He ran through the door.).
el tren(
trehn
)A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
