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"De lo contrario" is a phrase which is often translated as "otherwise", and "o" is a conjunction which is often translated as "or". Learn more about the difference between "de lo contrario" and "o" below.
de lo contrario(
deh
loh
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. otherwise
Te invito a la fiesta porque quiero que vengas, de lo contrario, no lo haría.I'm inviting you to the party because I want you to come, otherwise I wouldn't do it.
b. or else
Tendría que operarse, de lo contrario, irá perdiendo gradualmente la visión de ese ojo.You should have an operation, or else you'll gradually lose the sight of that eye.
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).