In this task, you are given a sentence in the Spanish language. Your task is to translate the Spanish sentence into the English language.

Durante la segunda mitad del siglo XX son varias las teóricas enfermeras que desarrollan diferentes definiciones sobre la enfermería. ¿Cuál de las siguientes características puede considerarse común a todas ellas?
During the second half of the 20th century there are several theoretical nurses who develop different definitions about nursing. Which of the following characteristics can be considered common to all of them ?