腕

wàn = w + an4

wrist / (squid, starfish etc) arm

腕 character breakdown

腕
- 宛
  - 夗
    - 㔾
      - 乚
      - ㇆
        
        一
        
        亅
    - 夕
  - 宀
    - 丶
    - 冖
- 月
  - 二
    - 一
  - ⺆
    - 丿
    - ㇆
      - 一
      - 亅

wǎn = w + an3

winding / as if / a surname

宛 = 夗 + 宀 : Mnemonic symbol: a winding machine.

Willy Walrus (w) built a winding machine (宛) to wind up sleeping bags (夗) in the anthill (an3). For his invention he got a honorary PhD degree and a graduation cap (宀), but as the winding machine winds up the sleeping bags his graduation cap gets in and ruins it.

月

yuè = yu + e4

moon / month / monthly / CL:個|个[ge4],輪|轮[lun2]

月 = ⺆ + 二 : Yu the Great (yu) is modelling a moon (月) in the elevator's bathroom (e4). He uses a stapler (⺆) to staple a lot of capacitors (二) together to form a moon shape, while the real moon is sitting for him.