vs 

QUICK ANSWER
"Si" is a form of "si", a conjunction which is often translated as "if". "Lo conozco" is a phrase which is often translated as "I know him". Learn more about the difference between "si" and "lo conozco" below.
si(
see
)
A conjunction is a word that connects words, phrases, clauses, or sentences (e.g., The cat and the dog slept.).
conjunction
a. if
Si llueve mañana, cancelaremos el pícnic.If it rains tomorrow, we will cancel the picnic.
a. whether
Preguntó si me estaba divirtiendo.He asked whether I was enjoying myself.
b. if
Paco quiere saber si Laura también va a asistir.Paco wants to know if Laura is also going to attend.
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
masculine noun
a. B
Primero lo oí en si menor.I first heard it played in B minor.
b. ti (solfége)
Practiquemos las escalas en orden inverso: do, si, la...Let's practice scales in reverse order: do, ti, la...
Copyright © 2025 Dictionary Media Group, Inc.
lo conozco(
loh
 
koh
-
nohs
-
koh
)
A phrase is a group of words commonly used together (e.g., once upon a time).
phrase
a. I know him
¿De qué conoces a Ramón? - Lo conozco de la escuela.Where do you know Ramon from? - I know him from school.
b. I know it
¿Conoces Uruguay? - Sí, lo conozco bien. He estado allí varias veces.Do you know Uruguay? - Yes, I know it well. I've been there several times.
c.
This refers to an idiomatic word or phrase for which there is no word-for-word translation.
no direct translation
A Juan lo conozco porque es amigo de mi hermano.I know Juan because he's a friend of my brother's.
Ese barrio lo conozco. Mis abuelos vivían allí.I know that neighborhood. My grandparents used to live there.
2.
A word or phrase used to refer to the second person formal “usted” by their conjugation or implied context (e.g., usted).
(formal)
(second person singular)
a. I know you
Tengo la sensación de que lo conozco de algo. ¿Hemos coincidido antes en otra conferencia?I have the feeling I know you from somewhere. Have we met before in another conference?
Copyright © 2025 Dictionary Media Group, Inc.