No Variable Names given from Lesson 16 onward

Not sure if it's just me but from lesson 16 onwards needed variable names, such as _cells_ or _number_ or _size_, aren't given anymore. And further down the road even the hints don't contain them.

While knowing how to generally type in the solution, finding the right variable names needed for the specific situation becomes a game of guess with a lot of trial and error if one doesn't want to peek at the solution right away, which greatly hinders the progress and just becomes frustrating at some point.
The tutorials in itself are great but guessing around which of all those variable names we collected so far are needed for this specific practice really drains the motivation.

Naming them inside the code or in the documentation along the functions would already be enough.