佶

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).

吉 = 口 + 士 : Mnemonic symbol: "Giga" stems from a Greek word for "giant", so I'll represent 吉 by a giant.

吉 = 口 + 士 : The giant just arrived at the space station and is very hungry. In each hand he holds Joan of Arc and the bachelor captive and robs them for their mandarins which he longs for.