渐新世

渐 = 斩 + 氵 : Joan of Arc (ji) didn't dispose of her empty water bottles (氵) for a long time. Instead, she just hoarded them in the anthill's bathroom (an4). Today she wants to get rid of the bottles: step by step (渐), little by little (渐) she cuts them down using a lawn mower (斩).

新 = 亲 + 斤 : Marie Curie and her bride are inspecting their wedding presents in front of the encampment. There's a brand new pair of barbells packed in plastic foil.

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.