Speaking a language is like an open-book test. In fact it’s better. Because not only do all the answers exist out there already, but you’re also allowed to see the test before you take it. And you can carry notes.
So don’t be clever. Cheat.
Boldly going somewhere you’ve never gone before — a new place or situation? The post office? The bank? A brothel 1? Take a cheat sheet! 2 Look up some domain specific terms or phrases (not too many — your cheat sheet needs to be big enough to be legible but small enough to be portable and therefore useful, like a 3″x5″ index card).
Have you ever watched an interview with an actor you otherwise respected and been struck by how dumb they sound? 3 How uneloquent? That’s because they’re not using a script. At all.
Stick to the script. Cheat if you can get away with it (which is almost all the time). And then, if the worst comes to the worst, just B.S. your way out of it.