All but english and french (my native language) are machine generated yes sorry about that but there is quite a bit of text with all the lessons so I can't afford man made translations at my scale.

Maybe I will find a middle ground and get translators just for the critical parts such as the challenges, or at least find a better way to translate parameterized strings like the one you are referring to.

EDIT: there is indeed an issue with some localized entries where the parameters are not placed properly, I will fix this for the next version