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"Pero" is a conjunction which is often translated as "but", and "o" is a conjunction which is often translated as "or". Learn more about the difference between "pero" and "o" below.
pero(
peh
-
roh
)A conjunction is a word that connects words, phrases, clauses, or sentences (e.g., The cat and the dog slept.).
a. but
Te quiero comprar algo, pero no tengo dinero.I want to buy you something but I don't have any money.
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
o, la o(
oh
)A conjunction is a word that connects words, phrases, clauses, or sentences (e.g., The cat and the dog slept.).
a. either...or
Terminarás tu tarea o por las buenas o por las malas.You're going to finish your homework either the easy way or the hard way.
3. (otherwise)
a. or
La residencia del presidente de los Estados Unidos, o Casa Blanca, fue construida en 1790.The residence of the President of the United States, or the White House, was built in 1790.
A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).