還是

还 = 不 + 辶 : Hamlet sees an early exhibit of king Leonidas' gladiator sandals in the airplane's kitchen. However, the exhibition is still not set up but in the progress of being set up, so there's a big sign showing that it's forbidden to touch the sandals.

是 = 旦 + 龰 : Mnemonic symbol: a skull, from "to be or not to be".

Sherlock Holmes (sh) starts his day in the space station's bathroom (Ø4) with a mug of coffee (旦). Holding a skull (mnemonic symbol for 是) in his hands, he asks himself "to be, or not to be" (是). He wonders if he can make the skull come back to life using lots of coffee, and injects coffee from his mug into the skull using a syringe (龰).

是 = 日 + 下 + 人 : Mnemonic symbol: a skull, from "to be or not to be".

Sherlock Holmes (sh) watches the Neanderthal Man (人) trying to climb to the sun (日) on a ladder (下) in the space station's bathroom (Ø4). Sherlock is afraid that he'll open the window, so he puts on a big skull (是) and scares him off.