This makes a lot of sense, actually. Definitely great for learning. You could do it the way Duolingo does it - on desktop, it allows for "Hard Mode", where it

This makes a lot of sense, actually. Definitely great for learning. You could do it the way Duolingo does it - on desktop, it allows for "Hard Mode", where it lets you type the responses freely. On mobile however, it doesn't let you do that (unless you're using the app).