心裡有數

心 = 乚 + 丶 : Marie Curie (xi) uses a shovel (乚) to dig a hole in front of the encampment ((e)n1). She wants to bury her heart (心). To the side are three petal leaves (丶), with which she wants to cover it afterwards.

里 = 土 + 田 : Mnemonic symbol: a sunflower. The 田 part looks like the blossom and 土 looks like the stem and leaves. Li Qingzhao (li) wants to put up a field (田) inside (里) the space station's living room (Ø3). First she puts some earth (土) here and there, and then she plants lots of sunflowers (里).

有 = 𠂇 + 月 : Mnemonic symbol: confetti.

In an act of revolution, with a pair of scissors (𠂇) Maud Younger (y) is cutting a paper moon (月) into tiny pieces in the outhouse's living room (ou3). There is (有) only confetti (有) left over.

数 = 娄 + 攵 : Sheldon Shrimp (shu) occupied a lunar mansion (娄) inside of the space station (Ø3) although he knows that it is to be torn down. Outside of his lunar mansion the construction (or rather destruction) workers are already counting (数) down from ten. When they count (数) zero, they will start taking down the whole thing with their sledgehammers (攵).