WHOLE CHARACTER
适shì, kuò
suitable; fitting; comfortable; just at the moment; by chance; just now (适才)
适 shì is fitting just right: 适合 'to suit', 舒适 'comfortable', 适应 'to adapt'. The rare kuò reading belongs to an old separate graph.
Modern shape taught as geometry: 舌 inside the walking wrap 辶. History is kept separate: the detailed 適 shì account names the old sound side 啻 (chì), not the modern 舌, and the reading kuò belongs to a separate old graph (𨓈).
OUTER FRAME: THE WALKING/MOVEMENT WRAP
辶chuò
walk; movement (from 辵)
The walking wrapper; a bound radical form, not a standalone page.
In 适: outer frame: the walking/movement wrap Shown with its documented or clearly limited role.
INNER: THE WRITTEN INNER PIECE
舌shé
tongue
Standalone meaning is kept separate from its role in other characters.
In 适: inner: the written inner piece Shown as the modern written piece; the historical sound side named in the source is 啻 (chì) — a different graph. shì shares the final -i and tone 4 with chì; the initials differ.