宇

yǔ = yu + Ø3

room / universe

宇 = 于 + 宀 : Yu the Great (yu) just earned her PhD in the space station (Ø3) and is proudly putting on her graduation cap (宀). She was measuring cosmic (宇) rays by investigating the traces they left in a honey jar (于) and is demonstrating her experiment for the camera.

宇 character breakdown

宇
- 于
  - 亅
  - 二
    - 一
- 宀
  - 丶
  - 冖

于

yú = yu + Ø2

to go / to take / sentence-final interrogative particle / variant of 於|于[yu2]

宀

mián = mi + an2

"roof" radical (Kangxi radical 40), occurring in 家, 定, 安 etc, referred to as 寶蓋|宝盖[bao3 gai4]

宀 = 丶 + 冖 : Mnemonic symbol: the strokes of this character look like a graduation cap (宀).

Marilyn Monroe (mi-) wants to cook in the anthill's kitchen (an2) but she's afraid of the ants. That's why she builds a bunker: she uses a saucepan lid (冖) as the base, constructs pillars out of petals (丶) and uses a graduation cap (宀) as the roof.

于

於

yú = yu + Ø2

(of time or place) in; at; on / (indicating any indirect relation) to; toward; vis-à-vis; with regard to; for / (indicating a source) from; out of / (used in comparison) than / (used in the passive voice) by

于 = 亅 + 二 : Mnemonic symbol: prepositions (in, at, on, to, ...) are what glue the sentence together. Honey is as sticky as glue, so I'll represent 于 by a honey jar.

Yu the Great (于) was assigned to repair the electronics of the space station's kitchen (Ø2), but instead he was snacking honey from a honey jar (于). Unfortunately his capacitor (二) got stuck in the honey and now he has to use a crowbar (亅) to lever it out.