古交市

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.

交 = 亠 + 父 : Linus Pauling, a famous scientist with a beret. Father Time commands Linus Pauling to hand over his beret to him in front of the aorta, but Joan of Arc comes to his rescue.

市 = 亠 + 巾 : Mnemonic symbol: a supermarket.

Sherlock Holmes (sh) started a supermarket (市) in the space station's bathroom (Ø4), but all he has for sale right now are berets (亠) and towels (巾). He should have opened it at the beach!