改

Right-side rap radical — the indexing radical, the side-form of 攴, depicting a hand holding a stick. Marks 改 as an active forceful action: a tap or strike that corrects/changes something. Same family of 攵-driven chars: 教 (teach), 收 (collect), 放 (release), 政 (govern), 数 (count).

Left-side 己 supplies the sound, with jǐ shifting to gǎi in 改 — a known j/g initial alternation in this phonetic series. 己 also adds a faint semantic flavor: 'change one's self' is exactly the most common use of 改 (改变 change, 改正 correct, 改善 improve). Phonetic family: 纪 (record), 起 (rise), 记 (note), 妃 (consort).