The word "完工" is a compound verb formed through a common Chinese morphological process called verb-object construction. It combines the verb "完" (wán), meaning "to finish" or "to complete", with the object "工" (gōng), which here means "work" or "a project". Literally, it describes the action of "finishing the work". Syntactically, the first character acts upon the second, creating a cohesive lexical unit that has been conventionalized to mean "to complete a project" or "to finish construction". This structure is analogous to English phrasal verbs, where two elements merge to form a single, specific meaning.