Three letters spelled the same hide two senses split by a single dot. With sin (שׂ), שׂ־ח־ק is to play, a game, or a role on stage. With shin (שׁ), שׁ־ח־ק is to wear down, to erode by friction. Modern Hebrew keeps them apart by the dot but the same consonants run through both. The play branch gives us the player, the actor, and the game; the erosion branch gives us "worn out", which neatly also means "exhausted". Verified against pealim, dot 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 two senses sort themselves across the binyanim: pa'al and its passive nif'al carry the erosion sense (shin), while the active pi'el carries playing and acting (sin). Same skeleton, the dot tells you which world you are in.
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.