Tone-specific realization of declarative question intonation in Mandarin Chinese

A central question concerns whether interrogative marking overrides or interacts with lexical tone. This study investigates how interrogative meaning is realized in Mandarin declarative questions, examining both fundamental frequency (F0) trajectories and syllable duration across lexical tones. Four Mandarin tones were elicited in short and long sentences under declarative statement and declarative question conditions and analyzed using generalized additive mixed models and linear mixed-effects models. Results show that interrogatives exhibit elevated F0 relative to declaratives, with the strongest divergence occurring at the sentence-final syllable. Crucially, interrogative marking is tone-sensitive. Tone 1 shows register raising and final contour modification; Tones 2 and 3 exhibit enhancement of their rising components while preserving tonal minima; and Tone 4 maintains its falling contour despite global pitch elevation. These findings indicate that interrogative prosody modulates rather than neutralizes lexical tonal identity. Duration analysis further reveals tone-dependent temporal organization. In long sentences, interrogatives show significant final-syllable lengthening for Tones 2-4 but not for Tone 1. Interrogative marking therefore involves coordinated modulation of pitch and timing, with maximal enhancement at the prosodic right edge. The findings support a hierarchical view of interrogative prosody in Mandarin under tonal constraints.