Several parts combine into one character.

One of the most fascinating cross-language differences in CJK colors. 青 covers what English splits into TWO different colors — blue AND green. The character originally meant "the color of fresh-sprouted grass / the color of indigo mineral", and ancient East Asians did not lexically distinguish blue from green. To this day, this color word causes confusion for English speakers learning Japanese and Korean. Identical across 繁體 / 新字体 / 简体, though traditional Korean uses 靑 (the older form with a slightly different bottom).

The blue/green ambiguity persists most strongly in Japanese: 青信号 (ao shingō) is the GREEN traffic light (Japanese law calls it "blue" because the original 1930s legal text predates color clarity). 青リンゴ (ao ringo) is a green apple. 青葉 (aoba) is fresh green leaves. Mandarin and Korean have largely shifted toward 緑 / 绿 (green specifically) for green things, but 青 still pulls double duty in fixed compounds and idioms.

Mandarin: qīng, level 1st tone. 青年 (qīngnián, youth — "the green age"), 青春 (qīngchūn, spring of youth), 青蛙 (qīngwā, frog), 青菜 (qīngcài, green vegetables), 青蓝 (qīnglán, indigo blue). The "youth / freshness" extension runs deep — 青春 anchors the entire vocabulary of coming-of-age.

Japanese: TWO on-readings — セイ (sei) is dominant in 青年 (seinen, young man), 青春 (seishun, springtime of youth — central concept in Japanese culture), 青空 (aozora — kun-reading, blue sky). ショウ (shō) survives in older compounds. Kun-reading あお.い (ao.i, blue/green) is essential everyday adjective. The compound 青空 (aozora, blue sky) and 青信号 (ao shingō, green traffic light) showcase the blue/green double duty.

青 also anchors a phonetic family seen in 晴 (clear weather), 清 (pure), 静 (quiet), 情 (emotion), 請 (request) — all sharing pronunciation roots.

Memory aid: fresh grass color — but in Japanese, that includes both green and blue.