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"O si" is a phrase which is often translated as "or if", and "por el contrario" is a phrase which is often translated as "on the contrary". Learn more about the difference between "o si" and "por el contrario" 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.