The idiom **容光焕发 (róng guāng huàn fā)** is formed through a classic Chinese metaphorical and parallel structure, where the first two characters **容光** ("facial radiance") and the last two **焕发** ("glow/emit brilliantly") form a complementary pair. Literally, **容** means "countenance," **光** means "light," **焕** means "glowing," and **发** means "to emit." Together, they create a vivid image where the radiance of one's face (**容光**) is described as shining forth brightly (**焕发**), thus figuratively conveying a meaning of someone looking exceptionally healthy, energetic, and radiant. This structure exemplifies how many Chinese idioms (chéngyǔ) combine concrete imagery in a parallel, reinforcing manner to express an abstract, positive state of being.