Left: leather 革 (Horned 廿 animals have a skin 口 of leather.), right: 2x earth 圭 = piled earth (cf. with road/street 街, where you walk 行 over piled earth 圭)
Mnemonic
The leather for the piled earth (= the street) is: the shoe!
A horned 廿 animal seen from above with a backbone 丨 and broad hips 一 has a skin 囗 of leather around its torso. - Also this radical 皮 stands for leather.
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