外匯存底

外 = 夕 + 卜 : There's a hole in the wall of the airplane's bathroom (ai4), and from outside (外), a bat (夕) wants to enter. Willy Walrus (w) is very afraid of bats, so he does his best to hinder the bat from entering with a voodoo staff (卜).

汇 = 匚 + 氵 : Helga Horse (hu) brought a collection (汇) of water bottles (氵) and a metal box (匚) to the Eiffel Tower's bathroom (ei4). Each bottle contains water from a different river. Finally the moment she's been waiting for arrives: As she empties each bottle into the metal box, she converges (汇) the water of all these rivers at once.

存 = 一 + 仔 : Mnemonic symbol: a floppy disc. Kitty Cat (cu) wants to protest against the law that women have to wear skirts, so wearing jeans (仔) she dances and plays a flute (一) in the encampment's kitchen ((e)n2) and records her demonstration on a floppy disc (存) to upload it later to her livejournal.

底 = 广 + 氐 : The space station's old concrete foundation has been broken up, and Dorothy Gale wants to send the remnants of the foundation back to the base on earth using parachutes.