Revisiting the nature and the context of T4 alternations: insights from disyllabic, trisyllabic and quadrisyllabic word/digit productions in Taiwan Mandarin.

The tone values of a Tone 4 (T4) syllable are conventionally assumed to change from '51' to '53' when the syllable is followed by another T4 syllable in Mandarin Chinese. Literature focusing on T4 alternation is still inconclusive regarding the contexts for the alternations and whether the phenomenon should be better categorized as tone sandhi (i.e.