What is tone sandhi?
Tone sandhi is the change of a tone to a different tonal contour when a syllable occurs in a particular environment. The dialects of some languages, such as Mandarin and Cantonese, have relatively few tone sandhi environments. Others, like the Min languages have as many tone sandhi as citation tones. And at the far extreme are the dialects of Wu and Jin that have separate sandhi for each single tone based on all the different kinds of combinations each tone could occur in.
