三项式

三 = 一 + 二 : Mnemonic symbol: Cartesian coordinate system with three (三) axes. Socrates (s-) is performing in front of the anthill (-an1). He created an electrical flute by attaching a large capacitor (二) to the flute (一), so that he can get the attention of all the people. Moreover, he's balancing on a Cartesian coordinate system (三). Unfortunately, only three (三) people stop to watch the performance.

项 = 工 + 页 : Mnemonic symbol: a necklace (项). Marie Curie (xi) lost her necklace in the anglepod's bathroom (ang4) and tries to get it out of the toilet again. Marie jotted down some calculations (项) on a sheet of paper (页) and uses a steel beam (工) as a lever to get his necklace out by putting the lever at the exact right position and the sheet of paper on top of the other side of the lever.

项 = 工 + 页 : Mnemonic symbol: a necklace (项). Marie Curie (xi) lost her necklace in the anglepod's bathroom (ang4) and tries to get it out of the toilet again. Marie jotted down some calculations (项) on a sheet of paper (页) and uses a steel beam (工) as a lever to get his necklace out by putting the lever at the exact right position and the sheet of paper on top of the other side of the lever.

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.