亻
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丿
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丨
:
Mnemonic symbol: Rosa Luxemburg. She's quite radical, and her name starts with "r", just like "ren2". Also, 亻appears at the left-hand side of characters, and Rosa is a leftist as well.
Robinson Crusoe (r) and Rosa Luxemburg (亻) are having their favorite snacks in the encampment's kitchen: Rosa is eating a banana (丿) and Robinson is eating a dinosaur bone (丨).
兆
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儿
+
丷
+
八
:
Mnemonic symbol: a vulture, as the ancient Greek observed vultures and deducted omens from their behavior.
James II of England (zh) wants to know whether his coronation and his proposed eight-year plan is under a good omen (兆) and watches a vulture (兆) inside of the aorta's bathroom (ao4). In fact the vulture is ridden by Sun Wukong (儿) who is fighting a mean crocodile (丷) by throwing eight-balls (八) at it. The crocodile easily smashes the eight-balls with its large jaw. James II of England deduces that this is not a very good omen.