Think of a vowel as a projectile launched by the consonant before it. In this word, the [k] at the back is like a spring-loaded lever popping out the ball of the [ɛ]. But it doesn’t get far – the lips cut it off, closing with an unreleased [p], and the vowel is kept in.
Kept in? If the past tense is kept, then the present must be kep, right? It keps the vowel?
No, no, keep your hat on. I know that kept is the past tense of keep. And kep looks more like kepi, a French military cap (the name of which comes from Swiss German käppi) – which actually sounds in French like English “KP,” which is not something a military person wants (it stands for kitchen patrol and means that today you’re doing scut work).
But guess what: kep is Northern and Scots English for the present tense of kept – but just when we’re talking about something being intercepted: stopped from falling or proceeding forward, by being blocked (as by throwing oneself in the way) or caught (as with the hands cupped). And guess what else: it comes from a backformation of a present form from the past tense form kept. Yep. It’s not that they don’t have keep. But this is kep.
There is, by the way, another kep – or, rather, KEP. It stands for kinetic energy penetrator: a projectile that does its damage not by exploding on impact but just by force of kinetic energy. Which means it’s heavy and is fired fast. Cannon balls were the original KEPs, but today a KEP will be in the line of an armour-piercing round, probably shaped like a thick arrow and made of very heavy metal. It’s something even metal armour inches thick can’t kep.
But if you want to use kep in real life, think of a person kepping a bullet, baseball, or thrown cream pie – or cup your hands and kep some pouring water or grain. Or sing along with Pretty Poison or Real Life, just slightly modified: “Kep me I’m falling…”