"Hoy es nuestro último día de vacaciones."
I disagree, in that the whole point of the exercise is to learn vocabulary and grammar, so you should translate the sentence as it is written, not a similar version you prefer.. "Today is the last day of our vacation" would be different in Spanish (just as it's different in English).
i would agree if all translations were literal, but i think you would agree there is a certain amount of inconsistency here. It's like sometimes Duolingo wants it translated lterally because they are testing you, and then other times ( for example: "lleva varias horas de trabajo" they want the meaning of the sentence).I agree with GrahamRawlinson on this one.
I got this wrong and i think here it is about learning the word meanings, not trying to figure out exactly what the perfect literal way to say something is. Especially since at times the computer seems to go with the sentence that makes more sense in English rather than a perfectly literal translation. So this going back and forth is confusing at times.