付ける
つける · tsukeru · JLPT N3 · verb-ichidan
to attach
📎 tsukeru sounds like stick 'er on: you attach it, you add it
付 = 亻 person + 寸 hand: a hand passing something on to a person, so it gets added to them. The same verb covers attaching a label, adding seasoning, and switching on a light (電気を付ける).
付 — person radical 亻 + hand 寸
付 originally pictured a hand (寸) reaching out to hand something to a person (亻), depicting the act of giving or delivering. The core sense 'to hand over, deliver, pay' has remained stable since ancient bronze inscriptions. It also serves as a phonetic component in characters like 附, 符, and 府.