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COMO TRADUCIR EN ..LOS CONOCI ....A INGLES

Los conocí en 1999 = I met them in 1999 / I came to know them in 1999

I agree, that's the best translation, "I met them..."

Note that "to meet" also translates to 'encontrarse.' Viviane specifies 'meeting for the first time' with a little bit of context (1999), or the "came to know them" translation.

Here's some examples that can help you clarify:

Los conocí lunedi, y nos hemos encontrados miercoles. = I met them for the first time on Monday, and we got together on Wednesday.

Nos appenas conocí hoy = We just met today. / We didn't know each other before today.

Other expressions that might work:

-We didn't know each other until today.
-We first met in January.
-Our friend Juan introduced us to each other.
-We haven't met yet. My name is Brian. (To introduce myself when the timing is a little bit late.)

I hope that helps!