空氣阻力

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.

Mnemonic symbol: a balloon. The Queen of Hearts is disappointed by her balloons. She expected them to float upwards, but in the space station's bathroom, They float randomly in all directions.

阻 = 且 + 阝 : Hostile aliens are seizing the space station! Inside (Ø3), the pope (阝) and Zapatista Zebra (zu) have constructed a barricade out of a few shelves (且). They will block (阻) the way of any alien which wants to seize the navigation bridge!

力 = ㇆ + 丿 : Mnemonic symbol: a power button.

Li Qingzhao (li) just had a shower in the space station's bathroom (Ø4) and wants to use the hair dryer, but there's no plug, just the bare end of the cable! She uses all her power to build an electricity plug, and for the two pins she uses a plough (㇆) and a banana (丿). Finally she hits a big power button (力) to turn the power on.