等差级数

等 = ⺮ + 寺 : Inside of the engine, Don Quixote is praying in front of a Buddhist shrine. He brought a bamboo stick as offer, and he lighted it at the very top. Now he's waiting for the stick to burn down so he can go home. However, the stick is very long: Don Quixote will have to wait for a long time.

差 = 工 + 羊 : Charlie Chapling is juggling steel beams in front of the ashram. A sheep is making an error bar graph representing Charlie's number of tries to juggle as long as possible without letting the beams fall down.

级 = 及 + 纟 : Joan of Arc (ji) closely investigates her newly arrived troops just inside the space station's entrance (Ø2). She ranks (级) them according to their level (级): First there is a silk worm (纟) which can at least shapeshift. On the next level, there is Yuwen Huaji (及), who has no comparable super power.

数 = 娄 + 攵 : Sheldon Shrimp (shu) occupied a lunar mansion (娄) inside of the space station (Ø3) although he knows that it is to be torn down. Outside of his lunar mansion the construction (or rather destruction) workers are already counting (数) down from ten. When they count (数) zero, they will start taking down the whole thing with their sledgehammers (攵).