Prounce it "K-nife" and you realise that it is in fact the French word "Canif". Around 80% of english words are almost identical. Virtually all words ending in -ion (station, traction, or -able, -ible and -al are, for instance. It has been said that English is just French spoken very badly. Why did my school teacher start from the premise that the two languages were so similar, rather than making it difficult with list of vocab, verb forms and so on.

The French mostly say “I am going to do something...” rather than use the future tense endings. Je vais diner. I am going to dine, or eat dinner. They dont even bother with ‘le’ or ‘la’ - they just tip their tongues at ‘l’ so fast you couldnt tell if it was a le or la. Same with ‘un’ and ‘une’. They dont say some gutteral ‘UGH’ or “OONE” just a subvocal ‘u’. 

Teachers jobs seem to be to justify their salaries. I was a maths teacher and I started from the premise that the kids could already do much of what they needed - there were quick ways to do things, approximations suit us most of the time, the rest of the time we have calculators or even other people. And I was teaching geometric axioms, quadratic equations and trigonometry. I know things have moved on since I taught a hundred years ago, but I’m guessing a little game theory, a smattering of statistics and a bit of analytical thinking about how to solve things might be useful.

Why not make an origami knife? I can think of two reasons, but nevertheless here is a link for you.