"Ella es la mujer más bonita de este país."
Translation:She is the prettiest woman in this country.
That's what I was thinking. I think the translation "She is this country's prettiest woman" makes sense, considering you "de" is typically used to depict possession; for example, "the pant's zipper" translates as "cremallera del pantalón," which literally translates back to English as "zipper of the pant."
not a teacher... I'm not sure it would, in Spanish. En español, they tend to prefer using "de" a lot more than "en" and these words are not interchangeable. Where you would normally use "in" in English, count on the possibility that in Spanish you might have to use "de". I don't know if I can explain the underlying logic, though. I hope this helps
Whereas, in a sentence like "Ella es más bonita que Anne," más bonita literally translates as more pretty; however, prettier is a much more suitable choice of words in this context; for example, you would say She is prettier than Anne instead of She is more pretty than Anne.