WHOLE CHARACTER
在zài
at; in; on (在家, 在职); to exist (存在, 健在); (progress marker) be doing (他在种地); to depend on (事在人为)
在 is at — where you are, whether things exist, and what you're doing right now.
ZDIC: 形声, 才 as the outer sound piece with 土 inside; the two pieces share strokes in the modern form, so the tree shows them without pretending clean separation.
SOUND (THE OUTER PIECE)
才cái
ability; only then
A standalone character; its sound side role in 在 shares the final ai only (initial and tone differ).
In 在: sound (the outer piece) ZDIC names 才 as the sound side; cái shares 在's final ai; the initial (c/z) and tone (2/4) differ.
MEANING (THE RADICAL 土, INNER)
土tǔ
earth; soil
Repeated in 垚.
In 在: meaning (the radical 土, inner) ZDIC names 土 as the meaning side; its strokes overlap the outer piece.