The Chinese word **推荐信** (tuījiàn xìn) is a compound noun formed through a straightforward and common grammatical structure in Mandarin, where the first element modifies the second. It combines the verb **推荐** (tuījiàn), meaning "to recommend," with the noun **信** (xìn), meaning "letter." Therefore, the compound follows a **modifier-head** (or attributive-head) construction, literally translating to "recommendation letter," where "recommendation" describes the purpose or type of "letter."