公因式

公 = 八 + 厶 : Mnemonic symbol from 公交车: a (magic) bus.

公 = 八 + 厶 : Gitta Giraffe has to deliver 100 eight balls to engine driving a magic bus. She is driving in front of the engine and because the load is so heavy, she is driving very slowly. Additionally, she tried to decrease the wind resistance by installing a large fake nose at the front of the bus.

因 = 囗 + 大 : Mnemonic symbol: the close reasoner René Descartes.

因 = 囗 + 大 : In front of the encampment, René Descartes, Maud Younger and a robot a starting a big rave. The robot sits inside a big box and is the master of ceremony, while René and Maud are dancing on the square. They started this rave to collect money for a good cause.

式 = 工 + 弋 : I'll use a specific style as mnemonic symbol: 哥特式, gothic.

Sherlock Holmes and the goth are celebrating a Viking festival in the space station's bathroom. They don't have trunks to throw around, so they use a steel beam. They also celebrate by practising archery. In zero gravity it is easy for them to set one world record after the next.