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"An" is an indefinite article which is often translated as "un", and "o" is a noun which is often translated as "la o". Learn more about the difference between "an" and "o" below.
an(
ahn
)An indefinite article is a word that indicates that a noun is not specific (e.g. a girl).
A preposition is a word that indicates the relationship between a noun and another word (e.g. He ran through the door.).
2. (each)
o(
o
)A noun is a word referring to a person, animal, place, thing, feeling or idea (e.g. man, dog, house).