替

Bottom is the sun radical (the entry indexes under 曰 'speak' which is graphically identical, square with a stroke inside). It marks the daylit setting in which one figure replaces another — a quiet, observed swap by daylight. The radical itself is a pictograph of the sun with a central stroke.

Top-left 夫 — pictograph of a grown man with a hairpin, marking adulthood. Paired with the second 夫 to its right, the two figures depict one person standing in for another, the core image behind 替 'to replace, to substitute'. Originally read as an ideographic compound: two men, one swapping places with the other.

Top-right 夫 mirrors the left one — the second figure in the pair. The reduplication is the whole point: it is the visible image of substitution, one person standing where another stood. The duplicated 夫 over 日 originally read as 'one man taking the daylit place of another' before the meaning generalised.