万人空巷

万 = 丆 + ㇆ : As mnemonic symbol I choose a neuron, since each neuron is said to connect to 10000 others.

万 = 丆 + ㇆ : Willy Walrus needs to dig up the floor in the anthill's bathroom, but he is tired of doing so manually with a plough. To make his life easier, he sets up a wind wheel for electricity, connects a neuron to the wind wheel and the plough to transmit the electricity and uses his new DIY electric plough to dig much faster.

人 = 丿 + ㇏ : Mnemonic symbol: Neanderthal Man (人). Robinson Crusoe (r-) is looking for snacks in the encampment's kitchen (-en2) when he suddenly spots Neanderthal Man (人). Neanderthal Man offers him a banana (丿), but Robinson Crusoe doesn't trust the present and pokes it with a finger (㇏).

空 = 工 + 穴 : Mnemonic symbol: an air conditioner

空 = 工 + 穴 : In front of the engine, Karl Koala found some very special cave paintings. Using steel beams he constructs a protective cover. He also installs air conditioning to make the best environment possible to preserve the cave paintings.

巷 = 共 + 巳 : Marie Curie (xi) unsuspectingly turns into a small alley (巷) in the anglepod's bathroom (ang4) when she is surprised by a communist (共) sitting on a snake (巳).