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"Who" is a form of "who", a pronoun which is often translated as "quién". "For whom" is a phrase which is often translated as "para quién". Learn more about the difference between "for whom" and "who" below.
for whom(
for
hum
)A phrase is a group of words commonly used together (e.g., once upon a time).
a. para quien
That is the man for whom the monument was built.Ese es el hombre para quien se construyó el monumento.
b. por quien
That is a leader for whom many people would be ready to fight.Ese es un líder por quien muchas personas estarían dispuestas a pelear.
who(
hu
)A pronoun is a word that stands in for a noun (e.g., she).
a. quién
Hello? Who is calling?¿Hola? ¿Quién llama?
I don't know who he is, but he looks a lot like my brother.No sé quién es, pero se parece mucho a mi hermano.
2. (relative)