QUICK ANSWER
"In the" is a phrase which is often translated as "en el", and "by" is a preposition which is often translated as "por". Learn more about the difference between "in the" and "by" below.
in the(
ihn
thuh
)A phrase is a group of words commonly used together (e.g., once upon a time).
a. en el (masculine) (singular)
A word or phrase that is masculine (e.g., el libro).
A word or phrase that is singular (e.g., el gato).
The clothes are in the closet.La ropa está en el armario.
b. en la (feminine) (singular)
A word or phrase that is feminine (e.g., la manzana).
A word or phrase that is singular (e.g., el gato).
The pizza is in the kitchen.La pizza está en la cocina.
c. en los (masculine or mixed gender) (plural)
A word or phrase used to refer to a group including masculine words or both masculine and feminine words (e.g., bienvenidos).
A word or phrase that is plural (e.g., los libros).
According to the law, there must be seat belts in the cars.Según la ley, debe haber cinturones de seguridad en los coches.
d. en las (feminine) (plural)
A word or phrase that is feminine (e.g., la manzana).
A word or phrase that is plural (e.g., los libros).
We are going camping in the mountains.Vamos a hacer camping en las montañas.
a. en el (masculine) (singular)
A word or phrase that is masculine (e.g., el libro).
A word or phrase that is singular (e.g., el gato).
I was born in the year 1990.Nací en el año 1990.
b. en la (feminine) (singular)
A word or phrase that is feminine (e.g., la manzana).
A word or phrase that is singular (e.g., el gato).
I have a meeting in the morning.Tengo una reunión en la mañana.
c. en los (masculine or mixed gender) (plural)
A word or phrase used to refer to a group including masculine words or both masculine and feminine words (e.g., bienvenidos).
A word or phrase that is plural (e.g., los libros).
The band began making music in the eighties.La banda comenzó a crear música en los años ochenta.
d. en las (feminine) (plural)
A word or phrase that is feminine (e.g., la manzana).
A word or phrase that is plural (e.g., los libros).
He begins working in the early hours of the day.Empieza a trabajar en las primeras horas del día.
a. del (masculine) (singular)
A word or phrase that is masculine (e.g., el libro).
A word or phrase that is singular (e.g., el gato).
Mount Everest is the tallest mountain in the world.El monte Everest es la montaña más alta del mundo.
b. de la (feminine) (singular)
A word or phrase that is feminine (e.g., la manzana).
A word or phrase that is singular (e.g., el gato).
The winner of the championship is recognized as the best team in the league.El ganador del campeonato está reconocido como el mejor equipo de la liga.
c. de los (masculine or mixed gender) (plural)
A word or phrase used to refer to a group including masculine words or both masculine and feminine words (e.g., bienvenidos).
A word or phrase that is plural (e.g., los libros).
This university is one of the best in the United States.Esta universidad es una de las mejores de los Estados Unidos.
d. de las (feminine) (plural)
A word or phrase that is feminine (e.g., la manzana).
A word or phrase that is plural (e.g., los libros).
The best teams in the divisions play in the playoffs.Los mejores equipos de las divisiones juegan en la fase final.
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.
