Sandhi
Mutation or sandhi is the fusion of sounds across word boundaries, or the alteration of sounds due to neighboring sounds or due to the grammatical function of adjacent words. It occurs particularly prominently in Sanskrit phonology, hence its naming with a word from that language, but most languages have it. Internal sandhi features the alteration of sounds within words at morpheme boundaries, as in sympathy (syn- + pathy).The alternation of English article "the" is also exhibits mutation, because of the difficulty of saying /ÃÂðə ÃÂæpl/ (the apple), we say /ÃÂðiː ÃÂæpl/ instead.
Mutation plays a crucial in all Celtic languages. Welsh has three mutation types, all affecting the initial consonant of a word:
- Lenition or softening, in which voiceless consonants become voiced, and voiced stops become fricatives.
- Nasal, in which sounds become their corresponding nasal, thus, p>mh, b>m, g>ng etc.
- Spirant mutation, in which k and g become the affricates.
The Sindarin language created by J. R. R. Tolkien has lenition patterns based on those of Welsh. A word becomes softened if it: is the second part of a compound, anything after an article, or the subject of a verb and next to it. Thus, we get certh, rune, and i gerth, the rune.
Most tonal languages have tone sandhi, in which the tones of words alter in complicated ways. For example: Mandarin has four tones: a high monotone, a rising tone, a falling-rising tone, and a falling tone. In the common greeting ni2 hao3, both words would normally have the falling rising tone. However, this is difficult to say, so the tone on ni3 mutates into ni2.