The upside of this is that you are learning how not to treat your own students
Llanfairpg beat me to it. Although this situation is not ideal, if you find that you really are stuck with it, at least learn from it!
As for using exactly the right words, I would probably try to take on board as much as you can. One thing I struggled with on the FIC was, when pattering an exercise, trying to squeeze the words in quick enough to be able to get the point across before the demonstration had finished. My instructor was very hot on using particular phrases, which always turned out to be 1/4 length of my own phrases even if the meaning was the same!
Now I teach CPL and IR, I still use many of the phrases I learnt on my FIC, and I've added a few others of my own, but I still try to keep them as short as possible, just as I was taught to do on the FIC.
FFF
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