"You understand the recipe."
Translation:Capisci la ricetta.
One of the systematic issue with Duo for me is the lack of the 'polite' you. If you do not know someone well, then you don't use the 'tu' form of the verb tu capisci but the polite form Lei capisce (written with a capital). Or so I have read. Anyway Lei capisce la ricetta is presently rejected by Duo.
So we get the habit of using the familiar form all the time.
But maybe my sources are outdated and this is OK?
Duo uses capitals in the lesson you refer to. There is only one on "Formal You" and it actually has more on formal greetings salve instead of ciao. Interesting what you say about the capitals though - I wonder if tu is becoming more widespread. I bet ciao is. That's the internet.
Seems whoever devises the Italian sentences has an odd conviction that the "voi" form is simply inappropriate for particular contexts. Surely, I could be telling more than one person at a given time that they all understand the recipe, say, if I were conducting a cooking class.