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"Por el contrario" is a phrase which is often translated as "on the contrary", and "o" is a conjunction which is often translated as "or". Learn more about the difference between "por el contrario" and "o" below.
por el contrario(
pohr
ehl
kohn
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trah
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ryoh
)A phrase is a group of words commonly used together (e.g., once upon a time).
1. (general)
a. on the contrary
Claro que no me molesta que hayas venido a verme; por el contrario, me alegra mucho.Of course I don't mind your coming to see me; on the contrary, I'm really pleased about it.
b. on the other hand
Tú eres todavía muy joven; por el contrario, yo ya estoy muy viejo.You are still very young; I, on the other hand, am very old now.
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).