This study investigated 5-year-old Mandarin-speaking children's comprehension of "wh"-questions, universal statements and free choice inferences. Previous research has found that Mandarin-speaking children assign a universal interpretation to sentences with a wh-word (e.g., "shei" 'who') followed by the adverbial quantifier "dou" 'all' (Zhou in Appl Psycholinguist 36:411-435, 2013). Children also compute free choice inferences in sentences that contain a modal verb in addition to a "wh"-word and "dou" (Zhou, in: Nakayama, Su, Huang (eds.) Studies in Chinese and Japanese language acquisition: in honour of Stephen Crain. John Benjamins Publishing Company, Amsterdam, pp 223-235, 2017). The present study used a Question-Statement Task to assess children's interpretation of sentences containing "shei" + "dou," both with and without the modal verb "beiyunxu" 'was allowed to,' as well as the contrast between sentences with "shei" + "dou," which are statements for adults, versus ones with "dou" + "shei," which are "wh"-questions for adults. The 5-year-old Mandarin-speaking child participants exhibited adult-like linguistic knowledge of the semantics and pragmatics of "wh"-words, the adverbial quantifier "dou," and the deontic modal verb "beiyunxu."