"My girlfriend has three new purses."
Translation:Mi novia tiene tres carteras nuevas.
Duolingo uses words over and over like it does so they are not a part of the lesson. Here, Duolingo is teaching the words, "carteras" and "nuevas" (and not "bolsa"). It could also introduce new words for colors at the same time, such as "marrón" or "morado" but that would be over doing it. Too much to learn at once. Thus the massive use of "verde", "manzana" and "perro" and the like.