> Explain to someone in the language you claim to be fluent in how you'd go about making a fire without any matches. (hint: you need to use words like tinder, kindling, flint, etc.)

I wouldn't be able to do this in my own native language (aside from "stone" and "stick", I'm clueless about the tools involved), let alone in a foreign one. I think this is way too specific to be a good test for fluency.