Regarding "fra", I found this explanation. Hope it helps.
Duo doesn't show the correct translation for "fra" here. Reported.
Probably. There are a couple idioms in the main skills, not just in the Idioms bonus skill.
Like in "Colours", they teach you the phrase Sono al verde. (I'm broke.)
Well, actually there is no context. But you can imagine it in a situation where someone has made a request: Teacher: "Your report is overdue. Bring it tomorrow, not in fifty years." This would not be unusual in English. Child: "I'll clean my room tomorrow." Mom: "Tomorrow not in fifty years." Sounds like something I've heard or even said. :)
I still cannot understand this man's pronunciation! It sounded like he said, cinquantani (one word) instead of the two distinct words and I could not distinguish the sentence's meaning. So I therefore wrote exactly what I heard. This is such an ongoing issue. I wish DL would soon fix this.
Then I believe this voice with this sentence should not be used in a Listening exercise (write what you hear), but rather a translation exercise, so as to Not confuse the new learners of Italian. You then can later test the learners with listening exercises when they have more Italian exposure to the spoken language. Do you agree?