成功 (chénggōng) is both a verb ('to succeed') and an adjective ('successful'), used for achieving a desired result in any context. It contrasts with 顺利 (shùn lì), which describes a process as smooth and without problems; a task can be 成功 even if not 顺利 (e.g., overcoming obstacles). It also differs from 完成 (wánchéng 'to complete'), which just means finishing, without implying success.