快要
kuài yào · HSK 2
almost
⏰ 快 = fast/soon + 要 = want/about-to → about to happen soon
快要 pairs 快 (fast, soon) with 要 (want, will, about to). Together they signal an action on the verge of happening — almost, nearly, just about to. Often paired with 了 at sentence end: 快要下雨了 = it's about to rain.
快 — heart radical 忄 + 夬 (phonetic)
快 is a semantic-phonetic compound. The heart radical 忄 carries the meaning, since the original sense referred to a feeling of pleasure or delight. The right side 夬 supplies the sound. The meaning later extended from 'pleased' to 'quick, fast', the dominant modern sense.
要 — west 覀 (top) + woman 女 (bottom)
Originally a pictograph of a woman with hands on her waist, meaning 'waist' (the original form of 腰). The top 覀 is a stylized depiction of the waist area, not the character for 'west'. Over time it was borrowed for the meaning 'to want, important', so 腰 (with 月 flesh radical) was created for the original 'waist' sense.