Three consonants carry one idea: setting in place so it is right and ready. Aim a weapon, direct an intention, prepare a meal, be correct, they are all the same gesture of putting things in their proper position. This is a hollow root: the middle ו drops out and reappears across the binyanim, which is why the four verbs look so different from each other. From it Hebrew built nakhon (correct), kavana (intention), hakhana (preparation), the prep-course mekhina, and even the everyday word for a car, mekhonit, a little "set-up machine". Every word is verified against pealim, niqqud included.
The same root runs through the verb system. Each binyan is a voice: it bends the one idea into active, passive, causative or reciprocal. Tap to hear.
Because the root is hollow (middle ו), the verbs reshape it differently: pi'el keeps a doubled ו (לְכַוֵּן), while hif'il contracts to a long i (לְהָכִין). The four binyanim line up by voice: nif'al = be ready/correct, pi'el = aim/set, hif'il = make ready (prepare), hitpa'el = get oneself ready. The passive partners pu'al and huf'al exist in the system but are not lexicalized here.
Same root letters, different noun moulds (mishkalim). The mould tells you the function: who does it, the act of doing it, or the thing produced.
Strip the prefixes, suffixes and vowels. Three consonants remain, and the meaning lives there.