古时候

古 = 十 + 口 : Mnemonic symbol: at least on German maps, this character actually resembles a cloister.

Oh no! Gitta Giraffe (gu) found that the golden cross (十) broke off of the cloister (古) in the space station's living room (Ø3)! She skewers a mandarin (口) on top of the cloister so that she can skewer the broken off cross back on to fix it.

时 = 寸 + 日 : The sun asks Sherlock Holmes out for a coffee just inside the entrance of the space station. Looking at his pocket watch, Sherlock sees he has time, winks and "thumbs up".

时 = 寸 + 日 : Mnemonic symbol: a giant pocket watch.

候 = 亻 + 侯 : The marquis and Rosa Luxemburg are exhausted and want to use the outhouse's bathroom. Unfortunately Hamlet is still busy caring for his wounds, so they have to wait until he is finished. They watch all the time and inquire again and again when they will be able to use the bathroom.