Tone Sandhi - What Is and Is Not Tone Sandhi

What Is and Is Not Tone Sandhi

Tone sandhi is compulsory as long as the environmental conditions that trigger it are met. It is not to be confused with tone changes that are due to derivational or inflectional morphology. For example, in Cantonese, the word "sugar" (糖) is pronounced tòng (/tʰɔːŋ˨˩/ or /tʰɔːŋ˩˩/, with low (falling) tone), whereas the derived word "candy" (also written 糖) is pronounced tóng (/tʰɔːŋ˧˥/, with mid rising tone). Such a change is not triggered by the phonological environment of the tone, and therefore is not an example of sandhi. Changes of morphemes in Mandarin to the neutral tone are also not examples of tone sandhi.

In Hokkien (Taiwanese), the words kiaⁿ (high tone, meaning "afraid") and lâng (curving upward tone, meaning "person") combine to form two different compound words with different tones. When combined via sandhi rules, kiaⁿ is spoken in basic tone and lâng in original tone (written in POJ as kiaⁿ-lâng). This means "frightfully dirty" or "filthy". This follows the basic tone sandhi rules. However, when kiaⁿ is spoken in original high tone, and lâng rendered in low tone (written kiaⁿ--lâng), it means "frightful". This derivational process is distinct from the semantically empty change of tone that automatically occurs when kiaⁿ is followed by lâng, and so is not tone sandhi.