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"Her" is an adjective which is often translated as "su", and "what is" is a phrase which is often translated as "qué es". Learn more about the difference between "her" and "what is" below.
her(
huhr
)An adjective is a word that describes a noun (e.g., the big dog).
1. (possessive)
a. su
Her children are very bright.Sus hijos son muy inteligentes.
I cannot stand her attitude any longer.Ya no puedo soportar más su actitud.
A pronoun is a word that stands in for a noun (e.g., she).
2. (personal)
what is(
wuht
ihz
)A phrase is a group of words commonly used together (e.g., once upon a time).