"We want a vacation."
Translation:Nosotras queremos unas vacaciones.
There is definitely an issue with plural and singular vacation. For a previous question, "las vacaciones" is used however the answer was "a vacation." For this one, "unas vacaciones" is used for "a vacation," however "las vacaciones" is not an acceptable answer. ¿Por qué???
"Una vacación" means "a vacation," and "unas vacaciones" means "some vacations," and that is the reason that "the vacations" (las vacaciones) is not accepted. The word "the" never means "a" or "some."
If a previous answer listed "las vacaciones" as "a vacation," it was probably a colloquial interpretation because the number of the noun switched from plural to singular. Unlike English, in which "vacation" is a singular number noun just as a location is a singular destination no matter how many people are involved–think: They are going on vacation–it is colloquial Spanish to give each individual their own vacation: Están yendo en sus vacaciones.
'Queremos una vacaciones.' is not accepted even though Duo asks for a vacation. Why is Duo's 'correct' translation unas (some) when that is not what is asked for?
You either use "una vacación" or "unas vacaciones", based on this you had one error and one typo.
According to DLE (http://dle.rae.es/?id=bDzHUaT), "vacación" is "1. f. Descanso temporal de una actividad habitual, principalmente del trabajo remunerado o de los estudios. U. m. en pl.". Please notice the end note, "U. m. en pl." which means that it is used more often in the plural ("usado más en plural").
The reason why the plural form... probably because if someone says "quiero una vacación" it will likely be understood that the speaker wants a job opening (from the less used meaning "4. f. p. us. Cargo o dignidad que está vacante.").