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"Bend" is a transitive verb which is often translated as "doblar", and "slope" is a noun which is often translated as "la cuesta". Learn more about the difference between "bend" and "slope" below.
bend(
behnd
)A transitive verb is a verb that requires a direct object (e.g., I bought a book.).
2. (to direct)
a. dirigir 
She bent her gaze to the horizon just in time to see the last rays of the day.Dirigió la mirada al horizonte justo a tiempo para ver los últimos rayos del día.
b. concentrar 
He bent his mind to planning the peace conference.Se concentró en planear la conferencia por la paz.
3. (to incline)
a. inclinar 
The baby bent his head to the side in wonder at the sight of the ladybug.El bebé inclinó la cabeza hacia un lado maravillado al ver la catarina.
A noun is a word referring to a person, animal, place, thing, feeling, or idea (e.g., man, dog, house).
4. (curve)
b. el ángulo (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).
We'll need a few bends in these pipes to get the water from the street up into the tank.Necesitaremos unos ángulos en estos tubos para subir el agua de la calle hasta el tinaco.
5. (nautical)
a. la gaza (F) (knot or loop)
(f) means that a noun is feminine. Spanish nouns have a gender, which is either feminine (like la mujer or la luna) or masculine (like el hombre or el sol).
Tie a bend in the rope to make it easier to attach the anchor line.Ata una gaza a la cuerda para que sea más fácil sujetar la línea de anclaje.
6. (heraldry)
a. la banda (F)
(f) means that a noun is feminine. Spanish nouns have a gender, which is either feminine (like la mujer or la luna) or masculine (like el hombre or el sol).
My family's coat of arms has a crimson bend running across it diagonally.El escudo de armas de mi familia tiene una banda de color carmesí que lo cruza en diagonal.
An intransitive verb is one that does not require a direct object (e.g., The man sneezed.).
8. (to curve)
b. hacer una curva 
The road bent into an incline and the fog merged with the forest.El camino hizo una curva hacia abajo en una pendiente y la niebla se confundió con el bosque.
9. (to submit)
bends
A plural noun indicates that there is more than one person, place, thing, or idea.
10. (illness)
a. la enfermedad de los buzos (F)
(f) means that a noun is feminine. Spanish nouns have a gender, which is either feminine (like la mujer or la luna) or masculine (like el hombre or el sol).
If you rise to the surface more quickly than your bubbles, you can get the bends.Si subes a la superficie más rápido que tus burbujas, te puede dar la enfermedad de los buzos.
b. el síndrome de descompresión (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).
You may panic and want to go up faster than you should, but that causes the bends.Podría entrarte el pánico y querer subir más rápido de lo que deberías, pero eso provoca el síndrome de descomprensión.
slope(
slop
)A noun is a word referring to a person, animal, place, thing, feeling, or idea (e.g., man, dog, house).
a. la cuesta (F)
(f) means that a noun is feminine. Spanish nouns have a gender, which is either feminine (like la mujer or la luna) or masculine (like el hombre or el sol).
You need to go up that slope until you reach the church, and then to turn right.Tienes que subir por esa cuesta hasta llegar a la iglesia, y entonces virar a la derecha.
b. la pendiente (F)
(f) means that a noun is feminine. Spanish nouns have a gender, which is either feminine (like la mujer or la luna) or masculine (like el hombre or el sol).
This slope goes down to a square where there are lots of restaurants.Esta pendiente baja hasta una plaza donde hay muchos restaurantes.
c. el gradiente (M) (Latin America)
(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).
Regionalism used in Latin America: all the countries in South America, Central America, and the Caribbean. Does not include Spain.
My house is just past that slope.Mi casa queda justo al otro lado de ese gradiente.
a. la falda (F)
(f) means that a noun is feminine. Spanish nouns have a gender, which is either feminine (like la mujer or la luna) or masculine (like el hombre or el sol).
We climbed the slope of the mountain so we could look out over the valley.Escalamos la falda de la montaña para poder tener una vista del valle.
b. la ladera (F)
(f) means that a noun is feminine. Spanish nouns have a gender, which is either feminine (like la mujer or la luna) or masculine (like el hombre or el sol).
There was a mountain goat on the slope of the hill above us.Había una cabra montés en la ladera del cerro que quedaba por encima de nosotros.
3. (sports)
a. la pista de esquí (F)
(f) means that a noun is feminine. Spanish nouns have a gender, which is either feminine (like la mujer or la luna) or masculine (like el hombre or el sol).
Do you like skiing? This area has some of the best slopes in the Rockies.¿Te gusta esquiar? En esta zona están las mejores pistas de esquí de las Rocosas.
b. la cancha de esquí (F) (Southern Cone)
(f) means that a noun is feminine. Spanish nouns have a gender, which is either feminine (like la mujer or la luna) or masculine (like el hombre or el sol).
The slopes were closed because there was no snow.Las canchas de esquí estaban cerradas porque no había nieve.
4. (angle)
a. la inclinación (F)
(f) means that a noun is feminine. Spanish nouns have a gender, which is either feminine (like la mujer or la luna) or masculine (like el hombre or el sol).
The slope of the roof allows the snow to slide off.La inclinación del tejado permite que la nieve se deslice.
b. la pendiente (F)
(f) means that a noun is feminine. Spanish nouns have a gender, which is either feminine (like la mujer or la luna) or masculine (like el hombre or el sol).
The river banks have a slope of seven degrees.Las orillas del río tienen una pendiente de siete grados.
a. la pendiente (F)
(f) means that a noun is feminine. Spanish nouns have a gender, which is either feminine (like la mujer or la luna) or masculine (like el hombre or el sol).
The slope of the line connecting the two points, or "m", is four thirds.La pendiente que conecta las dos líneas, o "m", es igual a cuatro tercios.
An intransitive verb is one that does not require a direct object (e.g., The man sneezed.).
a. inclinarse 
In the attic, the ceiling slopes to the ground on either side.En la buhardilla, el techo se inclina a ambos lados hasta tocar el suelo.
b.  no direct translation
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
From that point onwards, the path slopes down toward the lighthouse.De ese punto en adelante, el camino desciende hacia el faro.
The ground slopes off from the river toward the town on top of the mountain.El terreno asciende desde el río hasta el pueblo que está en la cima de la montaña.
A transitive verb is a verb that requires a direct object (e.g., I bought a book.).
a. construir en declive 
We sloped the driveway to keep the rainwater from puddling.Construimos la entrada al garaje en declive para evitar que se formaran charcos cuando llueve.