二十一世纪

二 = 一 : Mnemonic symbol: a capacitor, because the two strokes remind me of the symbol in electrical drawings. Albert Einstein (Ø) is experimenting with a capacitor (二) in the space station's bathroom (Ø4). He finds that it's uncomfortable to discharge a capacitor using two flutes (一).

十 = 一 + 丨 : Mnemonic symbol: a holy cross. Sherlock Holmes (sh-) is investigating a very strange thing he found in the kitchen of the space station (-2): A big pyramid made of ten (十) crosses (十), which are in turn made out of flutes (一) and dinosaur bones (丨).

Maud Younger (y) forgot her keys to the space station (Ø1), all she brought outside was her flute (一). She has no choice but to crash the door with the giant flute.

世 = 廿 + L : Mnemonic symbol: the WTO or WHO.

Sherlock Holmes (sh) is cleaning a flower pot (廿) under the shower of the space station's bathroom (Ø4) with a loofah (L) because he didn't quite understand a poster next to the shower from the WHO (世) explaining dangers arising from different germs.

In this case, L is for loofah.

纪 = 己 + 纟 : Joan of Arc finds the space station's bathroom full of silken threads. She even cannot accomplish much using a butcher's hook. She knows that the silk worms are responsible and thinks that soon it will be the era of the silk worms.