One root, one idea: beauty. The adjective יָפֶה (beautiful) is among the first words a learner meets, and יֹפִי is the everyday "great!" you hear all day in Israel. The same three letters become a verb two ways: in pa'al you become beautiful, in pi'el you make something beautiful. A small family, but it shows the system cleanly. Every word here 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.
The pair reads like a rule of Hebrew: pa'al is the inner change (I grow beautiful), pi'el is the outward act on something else (I make it beautiful). The passives and the causative hif'il are not lexicalized for this root.
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.