可是

可 = 丁 + 口 : Karl Marx (k) is challenging his abilities (可) in the elevator's living room (e3). He tries to force a nail (丁) into a mandarin (口), just by using his head. On top of that he tries to do so one thousand times, in order to create a bed of nails (mnemonic symbol for 可).

可 = 丁 + 口 : Alternative mnemonic symbol: kebab, from the pronunciation "ke". Karl Marx (k) is preparing a kebab (mnemonic symbol for 可) in the elevator's living room (e3). He also skewers mandarins (口) on the long steel nails (丁) and will only allow (可) his guests to eat the rest of the kebab if they eat their mandarins first.

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.