发音 (fā yīn) is both a verb ('to pronounce') and a noun ('pronunciation'), focusing on the act or quality of producing speech sounds. As a verb, it contrasts with 读 (dú), which means 'to read aloud' — 发音 emphasizes the sound itself, while 读 is about reading a text. As a noun, it differs from 语音 (yǔ yīn, the phonetic system of a language) and 口音 (kǒu yīn, a regional accent).