I have to analyze this sentence, but I don't even understand its meaning:
magister usus omnium rerum est optimus.
nom-s, ?, gen-p, gen-p, "est", nom-s
There's also "magister usus omnium est rerum optimus" in the text (different word-order).
My guess is "the teacher the experience of all things is the best", but this does not make any sense.
"magistri usus omnium rerum est optimus" (the teacher's experience of all things is the best) makes sense ...