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"A" is an indefinite article which is often translated as "un", and "by" is a preposition which is often translated as "por". Learn more about the difference between "a" and "by" below.
a(
ey
)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.).
A noun is a word referring to a person, animal, place, thing, feeling, or idea (e.g., man, dog, house).
3. (letter)
4. (grade)
a. el sobresaliente (M)
(m) means that a noun is masculine. Spanish nouns have a gender, which is either feminine (like la mujer or la luna) or masculine (like el hombre or el sol).
I got an A on all my exams.Saqué sobresaliente en todos los exámenes.
5. (music)
An abbreviation is the shortened form of a word or group of words (e.g., "UFO" = "unidentified flying object"; "p." = "page").
a. A
How many N is 1 A?¿A cuántos N equivale 1 A?
The intensity of this electric current is 10 A.La intensidad de esta corriente eléctrica es de 10 A.
by(
bay
)A preposition is a word that indicates the relationship between a noun and another word (e.g., He ran through the door.).
a. por
The bridge was destroyed by the flood waters.El puente quedó destruido por las inundaciones.
The house was built by an architect.La casa fue construida por un arquitecto.
a. de
We're reading a book by Octavio Paz in Spanish class.Estamos leyendo un libro de Octavio Paz en la clase de español.
b. al lado de
I waited by the door until my name was called.Esperé al lado de la puerta hasta que me llamaron.
a. por
The cowboy came by the old buffalo trail.El vaquero llegó por la vieja senda de los bisontes.
a. a
We’re going to go by my mom’s house for lunch on Saturday.Vamos a ir a la casa de mi mamá a comer el sábado.
a. mediante
The energy produced by fusion is emitted as light.La energía producida mediante fusión se emite como luz.
11. (according to)
b. conforme a
By the new rules, there is no parking allowed near the fire station.Conforme a las nuevas normas, está prohibido estacionarse cerca de la estación de bomberos.
12. (mathematics)
a. no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
The wind is blowing east by southeast.El viento sopla estesudeste.
We were sailing north by northwest.Navegábamos en dirección nornoroeste.
a. por
The new deck will measure ten feet by eight feet.La nueva plataforma tendrá una medida de diez pies por ocho.
a. por
Are you paid by the hour or by the job?¿Te pagan por hora o por trabajo?
She broke the record by two seconds.Batió el récord por dos segundos.
16. (with gerund)
a. no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
She ended by thanking everyone who had helped.Terminó dando las gracias a todos los que habían ayudado.
They lowered their prices a lot, and by doing so they expected to fill the store with customers.Bajaron muchísimo los precios, y con esto pretendían llenar la tienda de clientes.
An adverb is a word that describes a verb, an adjective, or other adverbs (e.g., to run quickly, very tired).
18. (past)
a. no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
Our neighbor passed by without saying hello.Nuestro vecino pasó sin saludarnos.
You don’t own the street. Let me by!No eres dueño de la calle. ¡Déjame pasar!
a. no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
I'll stop by later.Me paso más tarde por ahí.
Your dad came by today.Tu papá pasó por aquí hoy.
20. (on one side)
a. no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
Can you keep the dress by for me? I’ll come back and pay for it later.¿Me puede apartar el vestido? Volveré luego a pagarlo.
I have a little money put by for emergencies.Tengo ahorrado un poco de dinero para emergencias.
