After being marked Incorrect, I translated "Ella siempre usa vestidos" with 4 dictionary apps, 2 of which seem to give me idiomatic translations sometimes too. Got She always uses dresses 3 times
Then I put "She always wears dresses" through the same 4 apps. Got Ella siempre lleva vestidos 3 times.
In defense of "She always uses dresses" - hey, not all DL sentences necessarily make total sense, although apparently this usage is acceptable even though it sounds off in English. (I will always remember getting "the spider eats crabs". Grammatically correct, OK, but making sense? I think not.)
SpanishDict, which I find pretty reliable, gives "to wear" as one of the meanings of "usar": http://www.spanishdict.com/translate/usar.
Wordreference.com also gives "to wear" as a possible meaning of "usar" (and also gives some related, specialized meanings such "to be commonly worn" or "to be in fashion"): http://www.wordreference.com/es/en/translation.asp?spen=usar.
Spanish words do not map one-to-one onto English words. "Usar" can be (and sometimes is) used in Spanish where we would use "wear."
Incidentally, the primary meaning of "llevar" in Spanish is "to carry" or "to take." I'm sure many students are puzzled because "llevar" is also used to mean "to wear."
In Spanish you "usa" a cartera and now you also "usa" a vestido? Is "usa" the main/only Spanish word you use to describe fitting ones body into clothing? My search begins for a more descriptive word for "wearing" clothes than usa! But if that's what it is, then that's what it is! Gracias!
Following on from other comments above, does anyone know when it is better to use "usar" or "llevar" to mean "to wear"? Is it a regional thing? I learned "llevar" by a Peruvian lady who was teaching in the UK and tried to tell us both Spanish and South American terms, but didn't teach "usar"