Top: also/further 亦 (To understand this variation 亦 as red 赤, you can also/further do.) [red 赤: When earth (clay) 土 is burned 灬, the pottery becomes red 赤], bottom: once again 又 (image of a hand)
Mnemonic
(Did he work so much until the hand was blood-red?) A reddish hand stands for: making a change.
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