Functional head properties of the degree word Hen in Mandarin Chinese

•Hen-XP and XP exhibit different distributions.•Hen is a realization of the head of DegP, rather than a modifier.•The reduplicant of an adjective is also a realization of the head of DegP.•The hen-final construction is derived by short predicate raising.

Drawing on syntactic evidence, this paper shows that the functional projection DegP is attested in Mandarin Chinese, and the degree word hen ‘very’ heads DegP. The former finding is based on the fact that the string hen-XP exhibits a different distribution from XP. The latter finding is based on the facts that hen and adjective reduplication are in complementary distribution, and that hen can be stranded at the sentence-final position, like some other head elements in the language.