亻
=
丿
+
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).
周
=
⺆
+
土
+
口
:
Mnemonic symbol: a hula hoop. James II of England (zh) performs in front of the outhouse (ou1): he swings a hula hoop (周), juggles three mandarins (口) and balances a small heap of dirt (土) on his head. He cheated a little bit though, because he stapled the heap of dirt to his wig with a stapler (⺆).