正
=
一
+
止
:
Mnemonic symbol: a stick-figure with straight lines. James II of England (zh) really has to use the engine's bathroom ((e)ng4), but there's a stick-figure (正) blocking the stalls with a barrier (止). The stick-figure measures with a flute (一) whether James is tall enough to go. James stands very straight (正) to make himself as tall as possible.
male adult / the 4th of the 10 Heavenly Stems 天干[tian1 gan1] / fourth (used like "4" or "D") / small cube of meat or vegetable / (literary) to encounter / (archaic) ancient Chinese compass point: 195° / (chemistry) butyl
丁
=
一
+
亅
:
Mnemonic symobl: a nail. 一 is the head of the nail and 亅 is the shaft. The point of the nail is already a bit bent.
Dorothy Gale (di) balances a flute (一) on a crowbar (亅) in front of the engine ((e)ng1). For this trick, she wins the fourth (丁) place in an artists competition and gets a quarter (丁) of a pizza as prize. Unfortunately, there is a big nail (mnemonic symbol for 丁) on the pizza slice.