TSUMUGU · TOCFL 1 · 字
筆
筆 ＝ 竹 ＋ 聿
ㄅㄧˇ · bǐ
noun — a pen, a brush
字源 FORM — what the parts do
聿義a hand gripping a brushthe old word for brush, complete in itself
A hand grips the brush (聿) — that graph alone wrote brush; Qin usage added the bamboo (竹) of the shaft: 說文, 楚謂之聿，秦謂之筆. From the brush to every pen, and to what pens do: 筆畫、一筆錢.
故事 STORY — a scene to remember it by
竹（竹）管束上毫，手一握（聿），字落在紙上。
A bamboo (竹) shaft tipped with hair; the hand closes on it (聿), and characters land on the paper.
字源記憶法
意 · Meanings
(本義)毛筆— the writing brush
→原子筆、鉛筆— pens of every kind常用
⇒筆畫— a stroke
⇒一筆錢— a sum — one stroke of the ledger
(本義) original meaning · → ⇒ each arrow = one more step of extension
關 · Related
聿yùthe bare hand-and-brush — 筆 before the bamboo書＝ ＋ 曰shūthe same writing hand on top — the thing written