正負號

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.

负 = ⺈ + 贝 : Mnemonic symbol: an opossum (负鼠) who carries her babies on her back.

A few pals practice their cosplay on the space station's bathroom. They want to reenact the town musicians of Bremen, and so Frieda Fuchs stands at the bottom, the crab is on top of Frieda, the crane is on top of the crab, the opossum is on top of the crane, and the opossum carries her babies on her back.

号 = 丂 + 口 : Hamlet accidentally locked himself into the aorta's bathroom, together with a mandarin which he is extremely allergic against. His only rescue is the emergency breathing mask attached to the wall which he puts on immediately. There is also a trumpet to call for help with a bugle call, but Hamlet has to wear the breathing mask, so he can't give the bugle call in a normal way. Instead, he has to give the bugle call with his butt.