Well, I've got inspired to muse about how a language-learning video game would work, according to... how I'd like to make one... And at the same time I'm quite confident that it's an impossible challenge...

Anyway, the game presents you with the line "Wie heißt du?" You can click on each individual word and find out their literal translation "Wie" - "How", "heißt" - "are called", "du" - "you", and you can look at the translation of the whole sentense: "What is your name?"... Unbeknownst to you, based on what (if anything) you've clicked before giving your answer, the game estimates your proficiency. So if you had to click every word, it provisionally assigns you the level "absolute beginner". What it does with this information is adjust the text that it presents you with next. If you're an absolute beginner, you probably need those words repeated to you a few times, to remember them. So a character will present itself "Ich heiße Wilhelm." Then it'll repeat the word "heißen" several sentences later. It'll also continue checking whether you've clicked the word's translation again, and update your level and mastery of the word based on this information...

I don't know what sharing this idea does... I'm frustrated with my job, and frustrated with the impossibility of realizing this game, although in a different way, so maybe it's the fact that there is a dream there...