I don't know
Hay muchas palabras cuyo significado desconozco.
There are many words whose meaning I don't know.
Desconozco si él es español o argentino.
I don't know if he is Spanish or Argentinian.
I don't know the meaning.
Desconozco por qué me enfado de forma tan repentina y agresiva.
I don't know why I get angry so suddenly and aggressively.
Desconozco la razón de su ausencia.
I don't know the reason for his absence.
Desconozco si es español o argentino.
I don't know if he's Spanish or Argentinian.
Desconozco el estado de salud del Príncipe.
I do not know the state of the Prince's health.
— La maldición de la flor dorada (2006)
I don't know the details.
I don't know what motivates them.