"She has short hair"
How do you say: "She has short hair" I believe it is: Ella tiene pelo corto. Or is it Ella tiene pelo es corto.
"Tiene pelo corto." is the most natural way to say this. If you want to use passive voice and emphasize the hair (rather than the person) you could write a more complicated sentence, "Tiene pelo que es corto." but that sounds just as awkward in Spanish as the English, "She has hair that is short."
Gus what do you think of "Ella es de pelo corto?"
I think, it could be: Ella tiene pelo corto.
or: Ella tiene pelo que es corto.
(You can't ignore the Spanish "that" or "which" here)
The adjective "corto" after the noun pelo doesn´t mean that the corto is a subordinate clause. Romance languages(French, Spanish, Italian...) like to put the adjective after the noun, not like the Germanic languages(English, German...).
Ella tiene pelo es corto ...wrong
Ella tiene pelo, es corto (el pelo de ella).
Ella tiene pelo corto.
Ella tiene el pelo corto.
Ella lleva el pelo corto.
Ella trae el pelo corto.
All are very common usages.