永久性

永 = 丶 + 水 : Yu the Great just got the most romantic proposal ever! In engine, somebody prepared a water fountain and had a diamond ring floating on a petal leaf float over to her. Unfortunately Yu the Great doesn't know who the ring is from, as her lover drowned in the water fountain earlier that day.

永 = 丶 + 水 : Mnemonic symbol: as the advertisements tell us, diamonds are forever. I'll represent 永 with a diamond ring.

久 = ㇏ + 勹 : Mnemonic symbol: hourglass.

久 = ㇏ + 勹 : Joan of Arc and the elephant are visiting the outhouse, and they have been looking at the Mona Lisa for hours. Impatiently, Joan of Arc looks at her hourglass telling them that they have been standing there like that for three and a half hours, so she's poking the elephant with a finger to tell him to move on.

性 = 忄 + 生 : Marie Curie had a strong character since she was little. Even in her cradle in the engine's bathroom she was only playing with a flail.