‘又快又准’ is a common four-character adjective phrase meaning 'both fast and accurate' — it emphasizes the simultaneous presence of two highly valued qualities. The structure ‘又…又…’ (yòu… yòu…) is a correlative conjunction pattern used to link two adjectives or verbs, indicating that both traits apply equally and without contradiction. Here, ‘快’ means 'fast, quick, efficient', and ‘准’ means 'accurate, precise, on-target'. Together, they describe performance where speed does not compromise correctness — often used for skills like typing, translation, diagnosis, or sports.

This phrase carries positive connotation and is frequently heard in work, education, and technical contexts. It’s neutral in register — appropriate in both spoken and written Chinese — and commonly appears in praise, instructions, or evaluations. Unlike single adjectives, ‘又快又准’ functions as a compound descriptor, typically modifying nouns (e.g., 方法, 手法, 反应) or serving as a predicate after 是 or 很. It reflects a cultural appreciation for efficiency paired with reliability.