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"Fuerza" is a noun which is often translated as "strength", and "fortaleza" is a noun which is also often translated as "strength". Learn more about the difference between "fuerza" and "fortaleza" below.
la fuerza(
fwehr
-
sah
)A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).
a. strength
A mi hermano y a mí nos tomó toda la fuerza levantar la caja.It took all of my brother's and my strength to lift the box.
a. strength
Han demostrado mucha fuerza para enfrentar tantos problemas.They have shown a lot of strength in facing all of these problems.
a. force
La policía desalojó a los manifestantes por la fuerza.The police removed the demonstrators by force.
4. (power)
a. strength
La fuerza de su argumento convenció a su jefe a darle un aumento de salario.The strength of his argument convinced his boss to give him a raise.
5. (military)
a. force
La fuerza de ocupación cometió muchas atrocidades.The occupying force committed many atrocities.
la fortaleza(
fohr
-
tah
-
leh
-
sah
)A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).
a. strength
Se necesita mucha fortaleza para levantar esas botellas de diez galones.It takes a lot of strength to lift those ten-gallon bottles.
2. (building)
a. fortitude
Su fortaleza se desarrolló cuando estaba atrapado tras líneas enemigas.His fortitude developed when he was trapped behind enemy lines.