精通
jīng tōng · HSK 7
to be proficient in
🎓 精 refined + 通 thorough = refined all the way through = mastery
精 — rice 米 + blue/green 青 (phonetic)
A semantic-phonetic compound: 米 (rice) gives the meaning, while 青 supplies the sound. Originally referred to polished, refined rice — grain with the husk removed. The sense broadened to 'refined, pure, essence,' and later 'fine, skilled, spirit.'
通 — 辵 (辶) walk + 甬 yǒng (phonetic)
通 is a semantic-phonetic compound. The 辶 (chuò) component means 'walk' or 'movement', giving the meaning of going through or passing. 甬 (yǒng), originally depicting a hanging bell or a path, supplies the sound. Together they convey 'to pass through, communicate, connect'.